Answer:
c.(x+1)^2=10
Step-by-step explanation:
Completing the square:
We use the following relation:
[tex](x + a)^{2} = x^{2} + 2ax + a^{2}[/tex]
In this question:
[tex](x + a)^{2} = x^{2} + 2ax + a^{2} = x^{2} + 2x + a^{2}[/tex]
We have to find a.
[tex]2a = 2[/tex]
[tex]a = \frac{2}{2}[/tex]
[tex]a = 1[/tex]
[tex]x^{2} + 2x + 1 = (x+1)^{2}[/tex]
Thus, we have to add 1 on the right side of the equality.
We end up with:
[tex](x+1)^{2} = 9 + 1[/tex]
[tex](x+1)^{2} = 10[/tex]
So the correct answer is:
c.(x+1)^2=10
Solve for y=x squared -18 solve for x
Step-by-step explanation:
[tex]y = {x}^{2} - 18 \\ y + 18 = {x}^{2} \\ square \: root \: both \: sides \: \\ \sqrt{y + 18} = \sqrt{ {x}^{2} } [/tex]
[tex]x = \sqrt{y + 18} [/tex]
Answer:
√y + 18 = x
Step-by-step explanation:
Let us solve it now.
y = x² - 18
Take -18 to the left side
y + 18 = x²
Now remove the square of x
√y + 18 = x
Trapezoid ABCD is graphed in a coordinate plane,
What is the area of the trapezoid?
4
3
B
С
16 square units
O 24 square units
32 square units
48 square units
-5 4 3 2 -11
1 2 3 4 5 x
-5
Answer:
24 square units
Step-by-step explanation:
The formula for computing the area of a trapezoid is shown below:
As we know that
Area of a trapezium is
[tex]= \frac{1}{2} \times h(a+b)[/tex]
where
h = perpendicular height
The a and b = length of the parallel sides.
Now,
h = 2 - -2 = 4 units
a = 5 - -3 = 8 units
b = 3 - -1 = 4 units
Now placing these values to the above formula
So, the area of a trapezoid is
[tex]= \dfrac{1}{2} \times 4(8+4)[/tex]
[tex]= 2 \times 12[/tex]
= 24 square units.
Hence we applied the above formula so that the area of trapezoid could come
Some college professors make bound lecture notes available to their classes in an effort to improve teaching effectiveness. A study of business student's opinions of lecture notes. Two groups of students were surveyed - 86 students enrolled in a promotional strategy class that required the purchase of lecture notes, and 35 students enrolled in a sales/retailing elective that did not offer lecture notes. At the end of the semester :"Having a copy of the lecture notes was helpful in understanding the material." Responses were measured on a nine-point semantic difference scale, where 1="strongly disagree" and 9=" strongly agree." A summary of the results is reported in the follow:
Classes Buying Lecture Notes Classes Not Buying Lecture Notes
n1=86 n2=35
X1=8.48 X2=7.80
S21=.94 S22=2.99
a. Describe the two populations involved in the comparison.
b. Do the samples provides sufficient evidence to conclude that there is a difference in the mean responses of the two groups of the students? Test using α=.01
c. Construct a 99% confidence interval for (μ1-μ2). Interpret the result.
d. Would a 95% confidence interval for (μ1-μ2) be narrow or wider than the one you found in part c? Why?
Answer:
Step-by-step explanation:
a) The number of students sampled in both populations are large. We can assume that the populations are normally distributed. The populations are also independent.
b) This is a test of 2 independent groups. Let μ1 be the mean responses of students buying lecture notes and μ2 be the mean responses of students not buying lecture notes.
The random variable is μ1 - μ2 = difference in the mean responses of students buying lecture notes and the mean responses of students not buying lecture notes.
We would set up the hypothesis.
The null hypothesis is
H0 : μ1 = μ2 H0 : μ1 - μ2 = 0
The alternative hypothesis is
H1 : μ1 ≠ μ2 H1 : μ1 - μ2 ≠ 0
This is a two tailed test.
Since sample standard deviation is known, we would determine the test statistic by using the t test. The formula is
(x1 - x2)/√(s1²/n1 + s2²/n2)
From the information given,
x1 = 8.48
x2 = 7.8
s1 = 0.94
s2 = 2.99
n1 = 86
n2 = 35
t = (8.48 - 7.8)/√(0.94²/86 + 2.99²/35)
t = 1.32
The formula for determining the degree of freedom is
df = [s1²/n1 + s2²/n2]²/(1/n1 - 1)(s1²/n1)² + (1/n2 - 1)(s2²/n2)²
df = [0.94²/86 + 2.99²/35]²/[(1/86 - 1)(0.94²/86)² + (1/35 - 1)(2.99²/35)²] = 0.0706/0.00192021883
df = 37
We would determine the probability value from the t test calculator. It becomes
p value = 0.195
c) Since alpha, 0.01 < than the p value, 0.195, then we would fail to reject the null hypothesis. Therefore, at 5% significance level, the samples do not provide sufficient evidence to conclude that there is a difference in the mean responses of the two groups of the students.
d) The formula for determining the confidence interval for the difference of two population means is expressed as
Confidence interval = (x1 - x2) ± z√(s²/n1 + s2²/n2)
For a 99% confidence interval, the z score is 1.2.58. This is determined from the normal distribution table.
x1 - x2 = 8.48 - 7.8 = 0.68
z√(s1²/n1 + s2²/n2) = 2.58√(0.94²/86 + 2.99²/35) = 1.33
The confidence interval is
0.68 ± 1.33
The upper boundary for the confidence interval is
0.68 + 1.01 = 2.01
The lower boundary for the confidence interval is
0.68 - 1.33 = - 0.65
We are confident that the difference in population means responses between the students buying lecture notes and the students not buying lecture notes is between - 0.65 and 2.01
d) For a 95% confidence interval, the z score is 1.96.
z√(s1²/n1 + s2²/n2) = 1.96√(0.94²/86 + 2.99²/35) = 1.01
The confidence interval is
0.68 ± 1.01
The upper boundary for the confidence interval is
0.68 + 1.01 = 1.69
The lower boundary for the confidence interval is
0.68 - 1.01 = - 0.33
Therefore, a 95% confidence interval for (μ1-μ2) would be narrower. This is seen in the values in both scenarios.
Find the produce 2 1/3 times 3 1/2
Answer:
49/6 or 8 16/99
Step-by-step explanation:
2 1/3 *3 1/2 = (7/3*7/2)= 49/6
First convert to fraction form
then multiply across numerator to numerator and denominator to deominator
Simplify if needed
Turn to mixed fraction if needed
Use the compound interest formulas A = Pert and A = P(1 + ) to solve. Suppose that you have $11,000 to invest. Which investment yields the greater return over 10 years: 6.25% compounded continuously or 6.3% compounded semiannually? Show your work
Answer:
Continuously
Step-by-step explanation:
Compounded continuously:
A = Pe^(rt)
A = 11,000 e^(0.0625 × 10)
A = 20,550.71
Compounded semiannually (twice per year):
A = P(1 + r)^t
A = 11,000 (1 + 0.063/2)^(2×10)
A = 11,000 (1 + 0.0315)^20
A = 20,453.96
Please answer this correctly
Answer:
10-19 ⇒ 4
40-49 ⇒ 3
Answer:
10-19: 4 numbers
40-49: 3 numbers
Step-by-step explanation:
10-19: 11, 13, 17, 18 (4 numbers)
40-49: 41, 44, 47 (3 numbers)
A random sample of adult female reaction times has a sample mean of x¯=394.3 milliseconds and sample standard deviation of s=84.6 milliseconds. Use the Empirical Rule to determine the approximate percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds.
Answer:
The percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds is 99.7%.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 394.3 ms
Standard deviation = 84.6 ms
Use the Empirical Rule to determine the approximate percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds.
140.5 = 394.3 - 3*84.6
So 140.5 is 3 standard deviations below the mean.
648.1 = 394.3 + 3*84.6
So 648.1 is 3 standard deviations above the mean.
By the Empirical Rule,
The percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds is 99.7%.
What is the area of the obtuse triangle below?
A. 90 sq units
B. 23 sq units
C. 18 sq units
D. 45 sq units
Answer:
A. 90 sq. units
Step-by-step explanation:
5(18) = 90
Eleanor can drive an average of 374 Miles on one tank of gas. How many miles can she drive on 15 tanks of gas
Answer:
5,610 Miles
Step-by-step explanation:
To solve this you would need to multiply the average miles by how many tanks of gas she will use.
374 * 15 = 5,610
So, Eleanor can drive 5,610 miles with 15 tanks of gas.
What is the inverse of the given function f(x)=1/4x -12?
Answer:
[tex]f^{-1}(x)=4x+48[/tex]
Step-by-step explanation:
To find the inverse, solve for y:
x = f(y)
x = (1/4)y -12
x +12 = (1/4)y . . . . add 12
4(x +12) = y . . . . . multiply by 4
y = 4x +48 . . . . . . simplify
The inverse function is ...
[tex]\boxed{f^{-1}(x)=4x+48}[/tex]
Please answer this correctly
Answer:
0-4: Make it 2 units tall
5-9: Make it 5 units tall
10-14: Make it 1 unit tall
15-19: Make it 4 units tall
20-24: Make it 4 units tall
Step-by-step explanation:
0-4: 2, 2 (2 numbers)
5-9: 6, 7, 7, 8, 9 (5 numbers)
10-14: 14 (1 number)
15-19: 15, 16, 16, 18 (4 numbers)
20-24: 21, 23, 23, 24 (4 numbers)
What is the slope of the line given by the equation below?
y-20 = 5(x-2)
Answer:
5
Step-by-step explanation:
first you need to simplify this equation and put it in slope intercept form which is y = mx + b
after simplifying you will get y = 5x + 10
since the slope is m , the answer will be 5
What’s the correct answer for this question?
Answer:
B:
Step-by-step explanation:
According to theorem, "the angle in a semi-circle is a right angle" So,
<O = 90°
<M = 54
<K = 180-90-54
<OKM = 36°
Any help would be great
Answer:
88/57
Step-by-step explanation:
Answer: 88:57
Step-by-step explanation:
Length is 88 and width is 57
So the ratio is 88:57
Type your answers into the boxes.
There are 36 students in a class. The pie chart shows the colour of their hair.
Students' Hair Colours
40°
Red
Blonde
Dark
240°
How many students have blonde hair?
How many students have dark hair?
How many students have red hair?
Answer:
(a)24
(b)8
(c)4
Step-by-step explanation:
Number of STudents in the Class = 36
Angle representing Students with Red Hair =40 degrees
Angle representing Students with Blonde Hair =240 degrees
Therefore:
(a)Number of Students with Blonde Hair
[tex]=\dfrac{240^\circ}{360^\circ} \times 36\\\\ =24$ students[/tex]
(b)Number of Students with Dark Hair
Angle representing students with dark hair = 360-(240+40)=80 degrees
Therefore:
Number of Students with Dark Hair
[tex]=\dfrac{80^\circ}{360^\circ} \times 36\\\\ =8$ students[/tex]
(c)Number of Students with Blonde Hair
[tex]=\dfrac{40^\circ}{360^\circ} \times 36\\\\ =4$ students[/tex]
There are 8 students that have blond hair
There are 24 students that have dark hair
There are 4 students that have red hair
Please find attached the pie chart used in answering this question
A pie chart is a graph that displays information in a circle. The circle is divided into slices which represent a numerical proportion. The sum of angles in a pie chart is 360 degrees
To determine the number of students with a type of hair, use this formula :
(degree of the slice that represents the hair type / 360) x total number of students in the class
Degree of the slice that represents blond hair = 360 - (240 + 40) = 80
Students that have blonde hair = [tex]\frac{80}{360}[/tex] x 36 = 8
Students that have dark hair = [tex]\frac{240}{360}[/tex] x 36 = 24
Students that have red hair = [tex]\frac{40}{360}[/tex] x 36 = 4
To learn more about pie charts, please check : https://brainly.com/question/11433309?referrer=searchResults
A tree that is 10 feet tall is growing at a rate of 2 foot each year. A tree that is 14 feet tall is growing at a rate of 2/3 foot each year. What is the number of years it will take for both trees to be the same height, and what will their height be?
Answer:
after three years
Step-by-step explanation:
Please help. I keep getting this problem wrong . I need help please . I’ll mark you as brainliest if correct . Only answer if you know. Thank you
Answer:
The real number 'a' = 32
The real number 'b' = 0
Step-by-step explanation:
Product of a number of a number and its conjugate = a + bi
The number is = -4 + 4i
Conjugate of this number is = -4 - 4i
Product of the number and it's conjugate
= (-4 + 4i)(-4 - 4i)
= -4(-4 - 4i) + 4i(-4 - 4i) [By distributive property]
= 16 + 16i - 16i - 16i²
= 16 - 16(-1)
= 16 + 16
= 32
a + bi = 32 + (0)i
By comparing both the sides,
a = 32
b = 0
A survey was sent out to compare the proportion of adults who use their car horns when driving for two age populations (1=younger adults, defined as between 20 and 39 years old and 2 =older adults, defined as over 60 years old). The following data was obtained from those who responded.
Calculate the 90% confidence interval using the standard normal distribution. Note that 1 =0.52. P2= 0.35, and s.e.(P1-P2) =0.0338. Round to the fourth decimal point. Please enter you answer in the following format: (lower value, upper value)
Use the horn Use the horn
Group Yes No Total
1= younger adults 261 240 501
2= older adults 123 229 352
Answer:
The 90% confidence interval for the difference between proportions is (0.115, 0.228).
As the value 0 is not included in the interval, we can conclude that there is significant difference in the proportion of youger adults that use the horn and older adults that use the horn.
Step-by-step explanation:
We want to calculate the bounds of a 90% confidence interval.
For a 90% CI, the critical value for z is z=1.645.
The sample 1 (younger adults) , of size n1=501 has a proportion of p1=0.521.
[tex]p_1=X_1/n_1=261/501=0.5210[/tex]
The sample 2 (older adults), of size n2=352 has a proportion of p2=0.3494.
[tex]p_2=X_2/n_2=123/352=0.3494[/tex]
The difference between proportions is (p1-p2)=0.1715.
[tex]p_d=p_1-p_2=0.5210-0.3494=0.1715[/tex]
The pooled proportion, needed to calculate the standard error, is:
[tex]p=\dfrac{X_1+X_2}{n_1+n_2}=\dfrac{261+123}{501+352}=\dfrac{384}{853}=0.4502[/tex]
The estimated standard error of the difference between means is computed using the formula:
[tex]s_{p1-p2}=\sqrt{\dfrac{p(1-p)}{n_1}+\dfrac{p(1-p)}{n_2}}=\sqrt{\dfrac{0.4502*0.5498}{501}+\dfrac{0.4502*0.5498}{352}}\\\\\\s_{p1-p2}=\sqrt{0.0005+0.0007}=\sqrt{0.0012}=0.0346[/tex]
Then, the margin of error is:
[tex]MOE=z \cdot s_{p1-p2}=1.645\cdot 0.0346=0.0569[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=(p_1-p_2)-z\cdot s_{p1-p2} = 0.1715-0.0569=0.115\\\\UL=(p_1-p_2)+z\cdot s_{p1-p2}= 0.1715+0.0569=0.228[/tex]
The 90% confidence interval for the difference between proportions is (0.115, 0.228).
The area of a circle is 153.86 square meters. What is the diameter of the circle? Use 3.14 for π.
Answer:
14m
Step-by-step explanation:
The area of a circle is given by
A = pi r^2
153.86 = 3.14 r^2
Divide each side by 3.14
153.86 /3.14 = r^2
49 = r^2
Take the square root of each side
sqrt(49) = sqrt(r^2)
7 = r
We want the diameter which is twice the radius
d = 2r
d =2*7
d =14
Answer:
I just wanted to add on it is 14 i tried it on savaas and it worked
Step-by-step explanation:
uppose the correlation between two variables, math attitude (x) and math achievement (y) was found to be .78. Based on this statistic, we know that the proportion of the variability seen in math achievement that can be predicted by math attitude is:
Answer:
The proportion of the variability seen in math achievement that can be predicted by math attitude is 0.78, the same value as the correlation coefficient.
Step-by-step explanation:
The correlation coefficient r between this two variables is found to be 0.78.
This coefficient can be calculated as:
[tex]r=\dfrac{SSY'}{SSY}[/tex]
where SSY' is the sum of the squares deviation from the mean for the predicted value and SSY is the sum of the squares deviation from the mean for the criterion variable.
Then, the value of the coefficient r is giving the proportion of the variability seen in the criterion value Y that can be explained by the predictor variable X.
Answer:
r=SSY'/SSY
Step-by-step explanation:
8. A biotech company is looking for a user experience researcher to organize and report on some user experience data for a health and wellness app. They need to know the demographics of the users and the average time the app is open for each demographic. In the technical interview, you are asked to describe your approach to the initial analysis. When describing your analysis plan for the request, with what type of statistics would you tell the interviewer you would start your analysis
Answer:
Descriptive statistics
Step-by-step explanation:
Descriptive statistics describes and summarizes the basic features of a given dataset. It explains features from a collection of information, it is also said to be a form of summary statistics. Here data is characterized using its properties.
In this case, I was asked to describe my approach to the initial analysis. When describing the analysis plan for the request, I would tell the interviewer to start analysis using descriptive statistics.
f(x)=x^3+10x^2-25x-250
Answer:
-16x^5
Step-by-step explanation:
f(x)=x^3+10x^2-25x-250
f(x) = x^3-15x+x^2-250
f(x) = x^5-15x-250
f(x) = x^5 -x + 16
f(x) = -x^5+16
f(x) = -16x^5
// have a great day //
Consider two unique parallel lines. What aspects of
these two lines are the same? What aspects of these two
lines would have to be different? Explain your reasoning.
Answer:
The slope of two parallel lines will always be the same. If the slope was slightly different, then the lines would intersect at some point, which breaks the definition of parallel lines.
The y-intercepts of two parallel lines have to be different, or else the two lines would be the same line. If the y-intercept and the slope are the same, then the lines will essentially equal each other.
Answer:
Sample Response: Two parallel lines will have the same slope. The slopes of parallel lines have to be equal. The y-intercepts of those two lines have to be different, otherwise they would be the same line. The x-intercepts of the parallel lines would also be different.
Step-by-step explanation:
edge 2020
The sum of a number and twenty-one is sixty-four.
Answer:
43
Step-by-step explanation:
If X + 21 = 64
then subtract 64 by 21 and you get 43
write eight hundred and seven thousand, two hundred and five in figures
Answer:
807,205
Step-by-step explanation:
Take the eight hundred and seven thousand and express that has 807,000. Then, add the two hundred and five at the end to get 807,205
The given statement is written in figures 807,205.
The given statement is eight hundred and seven thousand, two hundred and five in figures.
We need to write the given statement as the number.
What are numbers?A number is a mathematical object used to count, measure, and label. The original examples are the natural numbers 1, 2, 3, 4, and so forth. Numbers can be represented in language with number words.
Now, eight hundred and seven thousand, two hundred and five=807,205.
Therefore, the given statement is written in figures 807,205.
To learn more about the numbers visit:
https://brainly.com/question/17429689.
#SPJ2
Which explains why the graph is not a function?
Answer:
56
Step-by-step explanation:
Joana wants to buy a car. Her parents loan her $5,000 for 5 years at 5% simple interest. How much will Joana pay in interest?
Answer:
1250
Step-by-step explanation:
5% of $5000 is 250
250X5= 1250
Which of the following is an arithmetic sequence?
Answer:
D
Step-by-step explanation:
An arithmetic sequence is a series of numbers that increases or decreases by a certain quantity every step. A is not an arithmetic sequence, since it alternates between 2 and -2. B is not an arithmetic sequence, since it does not grow constantly in one direction. C is not an arithmetic sequence, but rather a geometric one. D is an arithmetic sequence, decreasing by 3 with each step. Hope this helps!
convert 6 kilograms to grams
Answer:
6000 grams the formula would be multiply the mass value by 1000
Step-by-step explanation:
Answer:
6000 grams
Step-by-step explanation:
6 kilograms
To convert kg into grams, we multiply by 1000
So,
=> 6 * 1000 grams
=> 6000 grams
i need help asap!!!!!
Answer:
31 degrees
Step-by-step explanation:
Since RPS and QPR make up QPS, the sum of their angle measures must be 47. Therefore:
3x-38+7x-95=47
10x-133=47
10x=180
x=18
QPR=7(18)-95=126-95=31
Hope this helps!
