Answer:
1 5/8
Step-by-step explanation:
9/4x2/2=18/8
18/8-5/8=13/8,
so the answer will be 1 5/8, yes!
18 In 2013, approximately 1.6 million students took the critical Reading portion of the SAT exam. The mean score, the modal score, and the standard deviation were calculated to be 115, respectively. 496,430, a Which interval reflects 95% of the Critical Reading scores? (1) 430 t 115 496 115 (2) 430 t 230 (4) 496 t 230
The interval reflects 95% of the critical reading scores is 430 t 230.
What is intervals?
Interval is the period of time between two points.
As per the given scenario
1.6 million students took the critical Reading portion of the SAT exam. The mean score, the modal score, and the standard deviation were calculated to be 115, respectively. 496,430,
95% confidence intervals
(Mu - 6.7-Mu+6.7)
(430-115×2 , 430+115×2)
By adding or substracting
( 430-230, 430+230)
So interval (430±230)
Thus,
The interval= 430±230.
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A box of 15 cookies costs $9 dollar sign, 9.
What is the cost for 1 cookie?
Answer: 0.6
Step-by-step explanation:
9/15 = 0.6
$9 / 15 cookies = $0.6 cents per cookie
Daniela is trying to solve an equation for x. Original equation: 1/2 x + 3 = 7/2 x + 5 The result of Daniela’s first step was: 3 = 7/2 x - 1/2 x + 5 Describe the first step Daniela made for the equation.
The first step performed by Daniela was that she subtracted 1 / 2 x from both sides of the equation.
How to solve an equation?An equation is a mathematical statement that is made up of two expressions connected by an equal sign.
In other words, equations are mathematical statements containing two algebraic expressions on both sides of an 'equal to (=)' sign.
Therefore, Daniela is trying to solve an equation for x.
1/2 x + 3 = 7/2 x + 5
The variable of the equation is x. The variable of an equation is a number represented with letters.
Hence, the first step performed by Daniela is as follows:
Subtract 1 / 2 x from both sides of the equation
1/2 x + 3 = 7/2 x + 5
1/2 x - 1 / 2 x + 3 = 7/2 x - 1 / 2 x + 5
3 = 7/2 x - 1 / 2 x + 5
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if f(x)=2x²-6, then find f(4)
Answer:
Substitute x = 4 into the equation.
f(4) = 2(4)² - 6
= 2(16) - 6
= 32 - 6
= 26
5x4x5x3+56
help ma pls why they got such long multipictacion in -8th garde
[tex]\fbox{356}[/tex]
[tex](5\times4\times5\times3)+56[/tex]
[tex]5\times4=20\\5\times3=15\\20\times15=300[/tex]
[tex]300+56=356[/tex]
Answer: 356
Step-by-step explanation:
-start by grouping numbers into smaller portions (ex. the 5x5)
-5x5=25
-4x3=12
-Now we have 25x12.
-10x25=250, now add two more 25's
-250+50=300 or 25x12=300
-Add 56 to get 356
20
Use the box and whisker plot to answer the following question.
73
81 84
70
→
65 70 75
80
Low temperatures (°F)
85
87
王
90
What is the interquartile range IQR of the data set? (IQR = Q3 - Q1)
The interquartile range IQR for the given data set is IQR=10
What is block and whisker plot?A box and whisker plot, often known as a box plot, shows a data set's five-number summary. The minimum, first quartile, median, third quartile, and maximum make up the five-number summary. A box is drawn from the first quartile to the third quartile in a box plot. At the median, a vertical line passes through the box.
How do you calculate box and whisker plot?Finding the median, lower quartile, and upper quartile of a given set of data (Q2, Q1, and Q3) is the first stage in creating a box-and-whisker figure. Now that you know how to calculate the interquartile range (IQR). The distance between the upper and lower quartiles is known as the interquartile range.
Lower data set:
70 73 81 84
Q1=73+81/2=77
Middle data set
65 70 75 80
Q2= 70+75/2=72.5
Upper data set
85 87 90
Q3=87
IQR=Q3-Q1=87-77=10
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pls, can someone explain me the solution step by step :)
Answer:
4
Step-by-step explanation:
Given expression:
[tex]\left(2-\log_{\sqrt{2}}10\right)\left(2-\log_{\sqrt{5}}10\right)[/tex]
[tex]\textsf{Apply the radical rule}: \quad \sqrt{a}=a^{\frac{1}{2}}[/tex]
[tex]\implies \left(2-\log_{2^{\frac{1}{2}}}10\right)\left(2-\log_{5^{\frac{1}{2}}}10\right)[/tex]
[tex]\textsf{Apply the log rule}: \quad \log _{a^n}(x)=\frac{1}{n}\log _a\left(x\right),\:\quad \:a > 0[/tex]
[tex]\implies \left(2-\dfrac{1}{\frac{1}{2}}\log_{2}10\right)\left(2-\dfrac{1}{\frac{1}{2}}\log_{5}10\right)[/tex]
[tex]\implies \left(2-2 \log_{2}10\right)\left(2-2\log_{5}10\right)[/tex]
Rewrite 10 as 2 · 5 and 10 as 5 · 2:
[tex]\implies \left(2-2 \log_{2}(2 \cdot 5)\right)\left(2-2\log_{5}(5 \cdot 2)\right)[/tex]
[tex]\textsf{Apply the log product law}: \quad \log_axy=\log_ax + \log_ay[/tex]
[tex]\implies \left(2-(2 \log_{2}2+2\log_2 5)\right)\left(2-(2\log_{5}5 +2\log_52)\right)[/tex]
[tex]\implies \left(2-2 \log_{2}2-2\log_2 5\right)\left(2-2\log_{5}5 -2\log_52\right)[/tex]
[tex]\textsf{Apply log law}: \quad \log_aa=1[/tex]
[tex]\implies \left(2-2(1)-2\log_2 5\right)\left(2-2(1) -2\log_52\right)[/tex]
[tex]\implies \left(2-2-2\log_2 5\right)\left(2-2 -2\log_52\right)[/tex]
[tex]\implies \left(-2\log_2 5\right)\left(-2\log_52\right)[/tex]
Multiply:
[tex]\implies 4 \cdot \log_2 5 \cdot \log_52[/tex]
[tex]\textsf{Apply the log rule}: \quad \log _{a}(x) \cdot \log_{x}(a)=1[/tex]
[tex]\implies 4 \cdot 1[/tex]
[tex]\implies 4[/tex]
find S.I if p=1500,r=5percent ,t=2y6m
Answer: 487.5
Step-by-step explanation:
Formula for Simple interest is
S.I = (P×R×T)/ 100
so, we are given with
P = 1500 ; R = 5% ;
T = 2 years 6 months
*here we need to convert 6 months in to years
so,
6 months = 1/2 year
T = 6 year + 1/2 year = 13/2 years
Now putting these values in formula
We get;
S.I = (1500×5× 13/2) / 100
Ans : 487.5
What is the missing number for each fraction? 12 25 40
The Missing number for each fraction is ---
a) 3/7 = 12/28
b)5/8 = 25/40
c)3/4 =12/16
d)7/3 = 14/6
Fraction:
A fraction (from Latin: fracturs, "broken") represents a part of a whole or, more generally, any number of equal parts. When spoken in everyday English, a fraction describes how many parts of a certain size there are, for example, one-half, eight-fifths, three-quarters. A common, vulgar, or simple fraction (examples {1}/{2}} and ) consists of a numerator, displayed above a line (or before a slash like 1⁄2), and a non-zero denominator, displayed below (or after) that line. Numerators and denominators are also used in fractions that are not common, including compound fractions, complex fractions, and mixed numerals.
Given that
a) [tex]\frac{3}{7}[/tex] = 12/_
let x
3/7 = 12/x
3x = 84
x = 28
3/7 = 12/28
b) x/8 = 25/40
40x = 200
x = 5
5/8 = 25/40
c)3/4 = x/16
4x =48
x =12
3/4 =12/16
d)7/x = 14/6
42 = 14x
x = 3
7/3 = 14/6
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Help me solve it please
((3*3)²)²
Answer:
6,561
Step-by-step explanation:
((3*3)²)²
((9)²)²
(81)²
6,561
Answer:
Step-by-step explanation
answer:6561
3 times 3 = 9
9^2=81
81^2=6561
Max is already 224 miles into his road trip. if he is averaging 52 miles per hour and the trip is 640 miles total, how many more hours does he have left to drive.
Find the two solutions to the following equation:
x(x + 10) = 0
Answer:
The correct answer is (0) and (-10)
Step-by-step explanation:
The standard form of this equation is (x-a)(x-b)=0
so, here given equation is : x(x+10)=0
For solving the equation, equate both the LHS parts equals to RHS i.e. :
x(x+10)=0
x=0 & (x+10)=0 or x=(-10)
What i the lope of a line perpendicular to the line whoe equation i 3x-6y=90. Fully implify your anwer
The slope of line perpendicular to line 3x - 6y = 90 is -2.
Slope-Intercept form of equation => y = mx + c
Slope = m
Given equation,
3x - 6y = 90
x - 2y = 30
2y = x - 30
y = x/2 - 15
y = (1/2)x + (-15)
Here, slope = m1
= 1/2
For line perpendicular slope will be negative reciprocal of the slope of given line.
Therefore, slope of other line = m2
= -1/m1
= -2
Hence, slope of line perpendicular to line 3x - 6y = 90 is -2.
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38 is 40% of what number?
Answer:
95
Step-by-step explanation:
x = 38 over 0.4 = 95
38 over x 100=40%
Rachael’s Restaurant, a fast-food restaurant company, operates a chain of restaurants across the nation. Each restaurant employs eight people; one is a manager paid a salary plus a bonus equal to 4 percent of sales. Other employees, two cooks, one dishwasher, and four servers, are paid salaries. Each manager is budgeted $3,000 per month for advertising costs.
The cost incurred by Rachael's restaurant as fixed, variable or mixed are given below.
What is restaurant?
A restaurant is a location where you can consume food while paying for it. In restaurants, a waiter or waitress will typically bring your food to your table. Breakfast, lunch, and dinner are all offered at the restaurant. The restaurant's food was delectable, and the waitstaff was courteous.
Given:
Rachael’s Restaurant, a fast-food restaurant company, operates a chain of restaurants across the nation.
Each restaurant employs eight people; one is a manager paid a salary plus a bonus equal to 4 percent of sales.
Other employees, two cooks, one dishwasher, and four servers, are paid salaries. Each manager is budgeted $3,000 per month for advertising costs.
The cost incurred by Rachael's restaurant as fixed, variable or mixed are,
a. Advertisement c cost relative to number of customers Fixed
b. Rental cost relative to number of restaurant Variable
c. Cooks salaries relative to number of customer Fixed
d. Cost of Supplies (cups, plates, spoons, etc.) relative
to number of customer Variable
e. Manager's compensation relative to number of customer Mixed
f. Servers' salaries relative to number of Restaurants Variable
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Complete question:
Complete question is attached below.
suppose the confidence interval was (5.68, 7.92). what is the correct interpretation of this interval?
We are 95% confident that the true slope of the relationship between weight and number of gogles for all piknits lies between 5.68, 7.92.
The population parameter's (1 - α)% confidence interval denotes a probability of (1 -α ) that the interval contains the parameter's true value.
Or, the parameter's (1 -α )% confidence interval means that there is (1 - α)% certainty or confidence that the interval contains the genuine parameter value.
Assume that the weight's 95% confidence interval is (p1, p2).
The mean weight's 95% confidence interval
The likelihood that the true means fall within this range is 0.95.
95 of these intervals will contain the actual mean weight if 100 of these intervals are generated using 100 identical-sized samples.
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Complete question :
Suppose the confidence interval was (5.68,7.92). What is the correct interpretation of this interval? The true slope of the relationship between weight and number of gogles lies between 5.68 and 7.92 We are 95% confident that the true slope for the relationship between weight and number of gogles for our sample of piknits lies between 5.68 and 7.92. There is a 95% chance that the true slope of the relationship between weight and number of gogles lies between 5.68 and 7.92. We are 95% confident that the true slope of the relationship between weight and number of gogles for all piknits lies between 5.68 and 7.92.
a farmer plans to fence a rectangular pasture adjacent to a river (see figure). the pasture must contain 405,000 square meters in order to provide enough grass for the herd. no fencing is needed along the river. what dimensions will require the least amount of fencing?
If the farmer plans to fence a rectangular pasture adjacent to a river than the dimensions that is required for the least amount of fencing is length = 900 m and width = 450 m .
In the question ,
it is given that ,
the farmer is planning to fence the rectangular pasture adjacent to the river ,
the area of the pasture is = 405000 square meter .
let the length of the pasture = "y"
let the width of the pasture be = "x" ,
since only three side is fenced , the required perimeter is = 2x + y ;
given that area ⇒ x*y = 405000
y = 405000/x ;
So , the perimeter equation becomes ;
p = 2x + 405000/x
differentiating and equation to 0 we get ;
p' = 2 - 405000/x²
2 - 405000/x² = 0 ;
2x² = 405000
x² = 202500 ;
x = 450 , putting in perimeter equation ,
we get ; y = 900 .
Therefore , the dimension is length = 900 m and width = 450 m.
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A function of x is shown on the coordinate plane. Over which intervals is the function increasing ??
Quickest gets brainlest
Answer:
B
Step-by-step explanation:
The function is increasing anywhere the slope is positive. This corresponds to the intervals -4<x<-2 and 0<x<2. So, answer B is correct.
Graph the function f(x) = -3 log₂ (-x-4) - 8 on the
axes below. You must plot the asymptote and any two points
with integer coordinates.
The graph of the function is attached below:
The asymptote of the function is:
(-3 log(-x-4)/log2)-8 →∞ as x→ -4
What is meant by a function?Exactly one element of Y is assigned to each element of X in a mathematical function from a set X to a set Y. The sets X and Y are referred to together as the function's codomain and domain, respectively.
Al-Biruni and Sharaf al-Din al-Tusi were two Persian mathematicians who are credited with developing the earliest known approach to the concept of function. The basic conception of functions was the relationship between fluctuating quantities and other variables. An illustration of this is how time affects a planet's position. The idea was developed historically with the infinitesimal calculus towards the end of the 17th century, and until the 19th century, the functions that were taken into consideration were differentiable.
Given function is,
f(x)= -3 log₂ (-x-4) - 8
The graph of the function is attached below:
The asymptote of the function is:
(-3 log(-x-4)/log2)-8 →∞ as x→ -4
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the owner of a bike shop sells unicycels and bicycles and keeps inventory by counting seats ans wheels.one day, she conts 15 seats and 22 wheels. The equation repersenting the total number of seats is u+b=15 where u is the number of unicycels and b is the number of bicycles
The equation representing the total number of wheels is given as follows:
u + 2b = 22.
How to model the total number of wheels?This problem is modeled by a system of equations, for which the variables are given as follows:
Variable u: Number of unicycles.Variable b: Number of bicycles.There is a total of 15 seats, hence, considering that each of the objects have one seat, we have that:
u + b = 15.
There is a total of 22 wheels, and we have that:
An unicycle has one wheel.A bicycle has two wheels.Then the equation representing the total number of wheels is given as follows:
u + 2b = 22.
Missing InformationThe problem asks for the equation representing the total number of wheels in this problem.
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there are two investments options: option 1: an initial investment of $5 that increases by 50% every year. option 2: an intial investment of $0.01 that doubles every year part a write an equation for each option to model the value a of the account x years prt b explain which investment will eventually have the greater value.
f(t) = [tex]0.01 ( 2 )^{t}[/tex] is which investment will eventually have the greater value.
What investment means?
An asset or object purchased with the intention of generating income or appreciation is referred to as an investment. An asset's value increasing over time is referred to as appreciation.
When a person buys a product as an investment, they don't intend to utilize it right away; instead, they plan to use it to make money later on.
F(t) = [tex]a(b)^{t}[/tex]
option a - a = 5
b = 1.5
f(t) = 5(1.5)
option b - a = 0.01
b = 2
f(t) = [tex]0.01 ( 2 )^{t}[/tex]
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Mitch sells thingamabobs. His revenue is modeled by the function
R(h) = 5h+8 for every h hours he spends working. His overhead cost is
modeled by the function C'′(h) = h² + 7h − 16. After how many hours does
he break even?
The number of hours to breakeven will be 5 hiurs
How to calculate the breakeven?The breakeven is the point at which the cost and the revenue are equal.
Since Mitch sells thingamabobs. His revenue is modeled by the function R(h) = 5h+ + 8 for every h hours he spends working and his overhead cost is modeled by the function C'′(h) = h² + 7h − 16.
This wll be:
Revenue = Cost
5h + 8 = h² + 7h - 16
Collect like terms
h² + 7h - 5h - 16 = 0
h² - 2h - 16 = 0
Solving the equation will give h as 5.
The number of hours will be 5 hours.
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a scientist wants to determine whether or not the height of cacti, in feet, in africa is significantly higher than the height of mexican cacti. he selects random samples from both regions and obtains the following data.
Africa:
Mean = 12.1
Sample size = 201
Mexico:
Mean = 11.2
Sample size = 238
(a) Which of the following would be the correct hypothesis test procedure to determine if there is a difference between the mean height of two cacti?
-Two-sample test for proportions
-Two-sample t-test
- Paired t-test
(b) What is the value of the sample statistic to test those hypotheses? (2 decimal places)
(c) If the T test statistic is 2.169, and df = 202, find the p-value. (3 decimal places)
(d) Select the correct conclusion at alpha = 0.05.
-The null hypothesis is not rejected. There is insufficient evidence of a difference between the mean height of two cacti.
-The null hypothesis is rejected. There is sufficient evidence of a difference between the mean height of two cacti.
-The null hypothesis is not rejected. There is sufficient evidence of a difference between the mean height of two cacti.
-The null hypothesis is rejected. There is insufficient evidence of a difference between the mean height of two cacti.
(e) Mark the correct statement at alpha = 0.05:
-The test result is statistically significant.
-The test result is not statistically significant.
(f) Explain the type of error, in context, that might have been made.
-Type II error, which means the scientist concluded there is a significant difference between average height of cacti in Africa and cacti in Mexico, when in reality there is no difference.
-Type II error, which means the scientist concluded there is not a significant difference between average height of cacti in Africa and cacti in Mexico, when in reality there is a difference.
-Type I error, which means the scientist concluded there is a significant difference between average height of cacti in Africa and cacti in Mexico, when in reality there is no difference.
-Type I error, which means the scientist concluded there is not a significant difference between average height of cacti in Africa and cacti in Mexico, when in reality there is a difference.
(g) What would the p-value have been if we had done a two-tailed test? (3 decimal places)
The correct options for the given parts are as follows
(a) Two-sample t-test.
(b) x1 bar - x2 bar = 12.1 - 11.2 = 0.9
(c) p - value = 0.031
(d) The null hypothesis is rejected. There is sufficient evidence of a difference between the mean height of two cacti.
(e) The test result is statistically significant.
(f) Type I error, which means the scientist concluded there is a significant difference between average height of cacti in Africa and cacti in Mexico, when in reality there is no difference.
What is sample statistics?
Any number calculated from your sample data is referred to as a sample statistic (or simply a statistic). The sample average, median, sample standard deviation, and percentiles are a few examples. Because a statistic is based on data obtained through random sampling, which is a random experiment, it is a random variable.
a) Since there are two independent samples and we want to compare population means. We must use: Two-sample t-test.
b) The value of the sample statistic to test those hypotheses is:
x1 bar - x2 bar = 12.1 - 11.2 = 0.9
c) This is two-tailed test. For p-value, use excel formula =TDIST(2.169,202,2).
p - value = 0.031
d) Since p-value is less than 0.05, correct option is:
The null hypothesis is rejected. There is sufficient evidence of a difference between the mean height of two cacti.
e) Since p-value is less than 0.05, correct option is:
-The test result is statistically significant.
f) Since null hypothesis is rejected, we might have been made Type I error. The correct option is:
-Type I error, which means the scientist concluded there is a significant difference between average height of cacti in Africa and cacti in Mexico, when in reality there is no difference.
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There are 5 Thursdays and 4 Saturdays in the month of February in a year. Find the date of the first Monday of the month of march of that year?
Answer:
March 4
Step-by-step explanation:
The fifth Thursday must happen 4 weeks after the first one. That means that the 5th Thursday is 28 days after the first one.
Feb 1 + 28 days = Feb 29
Feb 1, Thursday
Feb 8, Thursday
Feb 15, Thursday
Feb 22, Thursday
Feb 29, Thursday
Mar 1, Friday
Mar 2, Saturday
Mar 3, Sunday
Mar 4, Monday
Answer: March 4
why was the pail pale
The pail was pale because it was most likely made from a light-coloured material such as plastic or metal.
It is not clear why the pail was pale. The phrase "the pail was pale" does not make sense in the context of the properties of a pail. Pails are typically made of metal, plastic, or some other type of material and do not have a color or shade.
It is possible that you meant to ask a different question or that the phrase "the pail was pale" was intended as a joke or a play on words. Without more context, it is not possible to provide a meaningful answer.
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(x - 5)(2x + 5y)(3x - 8)
Answer:
=6x3+15x2y−46x2−115xy+80x+200y
Step-by-step explanation:
What is -2/3 to the 5th power?
-2/3 to the 5th power is equal to -0.008. To do this, we first need to raise -2/3 to the 1st power.
-2/3 to the 5th power can be calculated by raising -2/3 to the 5th power. To do this, we first need to raise -2/3 to the 1st power. This is equal to -2/3. We then need to multiply this result by itself four more times (since it is to the 5th power).
-2/3 * -2/3 = 4/9
4/9 * -2/3 = -8/27
-8/27 * -2/3 = 16/81
16/81 * -2/3 = -32/243
-32/243 * -2/3 = 64/729
Therefore, -2/3 to the 5th power is equal to 64/729. To simplify this, we can divide the numerator and denominator by 64. This gives us 1/11.5 which is equal to -0.008.
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Can you help me with thisss
Answer:
B. 2x - 5000
Step-by-step explanation:
She makes x now.
2 times x is 2x.
2 times minus 5000 is 2x - 5000.
Answer: B
Answer:
B. 2x-5000
Step-by-step explanation:
2x, the 2 means you're going to times that sum by 2. Then you have to subtract 5000 from that which we don't know how much she will have so the equation would be: 2x-5000
Damon and Nicholas are racing to see who can get his community service hours for scouting completed first. Damon, who has already completed 2 hours, plans to volunteer for 2 hours per week going forward. Nicholas hasn't started yet, but plans to dedicate 3 hours per week to his volunteer project from now on. Before too long, the boys will be tied, with the same number of volunteer hours. How long will that take? How many hours will each boy have volunteered by then?
The number of hours when Damon and Nicholas will be tied is 2 hours.
The number of hours for the volunteer is 6 hours.
How long will it take for them to be at same project?An equation is the statement that illustrates the variables given. In this case, two or more components are taken into consideration to describe the scenario.
From the information, Damon, who has already completed 2 hours, plans to volunteer for 2 hours per week going forward. Nicholas hasn't started yet, but plans to dedicate 3 hours per week to his volunteer project from now on.
Let the number of hours be h.
Damon's equation will be 2 + 2h
Nicholas equation will be 3h
The number of hours to be tied will be:
2 + 2h = 3h
3h - 2h = 2
h = 2
The number of hours is 2.
The number of hours for the volunteer will be:
= 3h
= 3(2)
= 6 hours.
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Please help me!!!!!!!!!
The system of equations is:
28cm = 2*(W + L)
28.8cm = 2*(0.9*L + 1.2*W)
b) Solving that we will get L = cm and W = 6cm
c) The figure becomes a square of sides of 7.2cm
How to write the system of equations?First, let's define the variables:
W = width of the rectangle.L = length of the rectangle.Remember that the perimeter of a rectangle is:
P = 2*(W + L)
We know that the perimeter is 28cm, then:
28cm = 2*(W + L)
And if we decrease the length by 10% and increase the width by 20% the perimeter is 28.8cm, then
28.8cm = 2*(0.9*L + 1.2*W)
Then the system of equations is:
28cm = 2*(W + L)
28.8cm = 2*(0.9*L + 1.2*W)
We can isolate L on the first equation to get:
28cm/2 - W = L
14cm - W = L
Replacing that in the other equation we get:
28.8cm = 2*(0.9*(14cm - W) + 1.2*W)
28.8cm = 1.8*(14cm - W) + 2.4*W
28.8cm = 25.2cm + 0.6*W
28.8cm - 25.2cm = 0.6*W
3.6cm/0.6 = W = 6 cm
So the width is 6cm, then the length is:
L = 14cm - 6cm = 8cm
c) The modified dimensions are:
0.9*L = 0.9*8cm = 7.2 cm
The new width is:
1.2*W = 1.2*6cm = 7.2 cm
So the length is equal to the width, then the figure becomes a square.
Learn more about systems of equations:
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