How come this person didn’t divide EVERYTHING on the left by 2? I thought you had to...
Answers
The short answer is that algebra doesn't work that way. You wouldn't divide *everything* by 2, but every term that contains a factor of 2.
In the expression
2 (6x - 1) + 2 (2x + 5)
both terms have a factor of 2 (the 2 out in front of them). They're the ones that get canceled when dividing by 2:
(2 (6x - 1) + 2 (2x + 5)) / 2 = 2/2 (6x - 1) + 2/2 (2x - 5)
… = 1 (6x - 1) + 1 (2x - 5)
… = (6x - 1) + (2x - 5)
and so on.
Looking ahead, it turns out that the equation is solved by x = 7. This makes 6x - 1 = 41 and 2x + 5 = 19. So the equation is saying that, if you make these replacements,
2×41 + 2×19 = 120
If you divide *everything* on the left by 2, you end up with fractions:
(2/2)×(41/2) + (2/2)×(19/2) = 41/2 + 19/2
but 41 + 19 = 60, so the end result would be 30, but that's not the same as 120/2 = 60.
Related Questions
PLEASE HELP ME FILE IS ATTACHED
Answers
Answer:
Its below in the explanation
Step-by-step explanation:
2^2 = 4 so y=4 and x,y = 2,4
3^2 = 9 and x,y = 3,9
4^2=16 and x,y=4,16
Please give me brainliest
Answer:
2^2 = 4 so y=4 and x,y = 2,4
3^2 = 9 and x,y = 3,9
4^2=16 and x,y=4,16
Step-by-step explanation:
A tank that holds up 10 gallons. when its active, a drain empties water from the tank at a constant rate, when Jada first see the tank, it contains 7 gallons of water. three minute later the tank contains five gallons of water.
At what constant/rate is the amount of water changing in the tank?
Answers
Answer:
-2/3 gallon/minute
Step-by-step explanation:
In three minutes the water volume has decreased by 2 gallons (7 less 5 is 2). The unit rate of decrease of the amount of water in the tank is thus:
- 2 gallons
------------------- = -2/3 gallon/minute
3 minutes
A family is going on a trip for 3 days. The total cost for the hotel is $369. One hundred dollars a day was budgeted for entertainment. How much will each day of the trip cost?
Answers
Answer:
223
Step-by-step explanation:
368 divided by 3= 123
123+100= 223
Three numbers are in the ratio 3:9:10. If 10 is added to the last number, then the three numbers form an arithmetic progression. What are the three numbers?
Answers
Answer: 6,18,60
Step-by-step explanation:
Don't really know tbh
Answer:
6, 18, 20
Step-by-step explanation:
your welcome
Will the product be more or less than 2 7/8 ?
Answers
Answer:
Im pretty sure the the product will be less than 2 7/8.
I think the answer will be 23/72
hey can someone please confirm my answer? i got D but it was a guess because i’m not confident in my graphing skills yet
Answers
Answer:
the answer is d
Step-by-step explanation:
A student scores the following marks in 10 tests
3,7,x,7,12,9,10,4,2,5
If the mean mark is 6, calculate the value of x.
Answers
Explanation=
10*6 = 60
3+7+7+12+9+10+4+2+5= 59
60-59=1
HELP I NEED HELP ASAP
A triangle has a perimeter of 15 feet. Side B is one foot longer than side A. Side C is two feet longer than side A. What is the length of each side.
Answers
Answer:
Side A = 4
Side B = 5
Side C = 6
Step-by-step explanation:
In the following equation, variable a is the length of Side A
a + (a + 1) + (a + 2) = 15
a + a + a + 1 + 2 = 15
3a + 3 = 15
- 3 - 3
3a (÷ 3) = 12 (÷ 3)
a = 4
Side A = 4
Side B = (a + 1) = (4 + 1) = 5
Side C = (a + 2) = (4 + 2) = 6
Billy has 8 red marbles, 6 blue marbles, and 4 green marbles in a jar.
What is the probability that Billy would select a red marble?
A. Between 10% and 20%
B. Between 20% and 30%
c. Between 30% and 40%
D. Between 40% and 50%
Answers
Answer:
A
Step-by-step explanation:
pick A cause 8 6 and 4 = 18
the total marbles are 18 so you divided 18 and 100 to get 5.55, then you multiply by the number of marbles and get 44.4
hope this helps
Find the 12th term given the arithmetic sequence: an = -5n +32
Answers
Step-by-step explanation:
step 1. a12 = -5(12) + 32
step 2. a12 = -60 + 32
step 3. a12 = -28.
What is the scale factor of Figure B to Figure A in the simplest form?
Answers
simple just multiply 10X25X21.5 for A and the same for B
The dimensions of a rectangle are x+3 and x+4. The area of the rectangle is 72. Set up an equation that models this rectangle and solve in order to determine the value of x.
Answers
Answer: x = 5
Step-by-step explanation:
The area of a rectangle is the length times the width. Since the dimensions are given as functions of x, youre going to have to use FOIL to combine them, then set that answer equal to the given value of 72.
l*w = (x+3)*(x+4) = x^2 + 7x +12 = 72
Subtract 72 on both sides. There is a reason why we'll do this instead of subtracting 12. The quadratic formula will help us to solve for x.
x^2 + 7x - 60 = 0
Apply the quadratic formula
[tex]\frac{-7 (+/-)\sqrt{7^2-(4)*(1)*(-60} }{2*1} =\frac{-7(+/-)17}{2}[/tex]
We cant have a negative x value because that would result in negative dimensions and a negative area, which is impossible in this context. So you want to add the 17 instead of subtracting it.
x = 5 and x = -12
An alternate way is just factoring the trinomial to:
(x+12)(x-5) = 0
what is 5 3/4 subtracted by 5/8
Answers
Answer:
[tex]5\frac{1}{8}[/tex]
Step-by-step explanation:
5 3/4 = 23/4
(23/4)2 = 46/8
46/8 - 5/8 = 41/8 = 5 1/8
THE QUESTION IS ABOVE
Answers
Answer:
The box would be 14
Step-by-step explanation:
It would be 14 because 7/14 is equal to 1/2. And 2/4 is also equal to 1/2.
Answer:
7/14
Step-by-step explanation:
Have a nice day.....
R4 = 74 what does R equal??????????????\
Answers
Answer:
R = 18.5
Step-by-step explanation:
Answer: 18.5
Step-by-step explanation: Divide 74 by 4
Jonah had 3/4 cup of water in his cup. He drank 1/2 cup of water. How
much water did he have left?
Answers
Answer:
1/4th Cup left
Step-by-step explanation:
1/2 cup is equal to 2/4 cup, so subtract that from 3/4th and you end with 1/4th
Help with this and I will give you the brainiest and you get 10 points
Answers
Answer:
1.-22
2.2
3.48
4.3b
5.1+5v
6.2m+20
7.p=-9
8.x=8
The time,
T
(seconds), it takes for a pot of water to boil is proportional to the amount,
A
(litres), of water.
It takes 180 seconds to boil 2.8 litres of water.
Work out how long it takes (to the nearest second) to boil 2.2 litres.
Answers
Answer:
The time it takes to boil 2.2 litres of water is approximately 141 seconds
Step-by-step explanation:
The given parameters are;
The relationship of the variables, T and A is a proportional, therefore, we have;
T ∝ A, or T/A = k = Constant of proportionality
The time it takes to boil 2.8 liters of water = 180 seconds
∴ When A = 2.8 litres, T = 180 seconds, from which we have;
k = T/A = 180 s/(2.8 L) = 450/7 s/L
k = 450/7 s/L
When A = 2.2 litres, we have;
T/A = k
∴ T = k × A
Plugging in the value for both 'k', and 'A' when A = 2.2 litres, gives;
T = k × A = 450/7 s/L × 2.2 L = 990/7 s = 141.[tex]\overline{428571}[/tex] s
The time it takes to boil 2.2 litres of water, given a direct proportionality relation is, T = 141.[tex]\overline{428571}[/tex] seconds ≈ 141 seconds given to the nearest second.
Solve the following equation: 4(x + 2) - 17 = 35
A: -11
B: 25/2
C: 15
D: 11
Answers
Answer:
D: 11
Step-by-step explanation:
4(x + 2) - 17 = 35
4x+8 - 17=35
4x-9=35
4x=35+9=44
x=44/4=11
PLEASE HELP!! ASAP WILL GIVE BRAIN!! AFTER SOLVING QUESTION, GIVE THE REASON(SSS
SAS
ASA
AAS)
Answers
last option:-
∆HOG is congruent to ∆ATCReason:- ASA
Hope it helps ⭐⭐⭐please help!
Megan has a bag with 8 red cubes, 3 yellow cubes, and 5 green cubes. What is the probability she will pick a red cube, keep it, and then pick another red cube?
Answers
Answer:
1st time: 50% chance or 8/16 chance
2nd time: 46% chance or 7/15
I can try again if its wrong
Answer:
7/30
Step-by-step explanation:
8/16 that she picks a red cube.
7/15 that she picks another red cube after keeping the first red cube.
multiply 8/16 (1/2) times 7/15 to get 7/30 as your final answer
I NEED THE NOE HURRY!!!!!!! i will mark u Brainliest
At most, Kyle can spend $50 on sandwiches and chips for a picnic. He already bought chips for $6 and will buy sandwiches that cost $4 each. Write and solve an inequality to show how many sandwiches he can buy. Use s to represent the number of sandwiches. Write your final answer in a complete sentence.
Answers
I need help with math if you don't know the answer get out of the question and don't answer it and give the wrong answer or some link or even say "I don't know" or anything like that it's not fair to me cause it a waste of my points I will report your if you do that :) have a nice day and stay safe
Answers
Answer:
13 1/3 pounds
Step-by-step explanation:
Hi! Each bad weighs 2 2/3 pounds. There were 5 bags bought so we multiply. Here is the expression:
2 2/3 x 5 = x
Now we need to convert 2 2/3 into an improper fraction, which is 8/3.
Easy! Now
8 5 40
- x - = -
3 1 3
*I tried to set it up like fractions.*
Simplify 40/3 and you get 13 1/3
HELP
ILL GIVE THE BEST ANSER 100 POINTS!!!!
Answers
awnser im believe it is 24 i think
Answer:
20 units square
Step-by-step explanation:
do the Pythagoras theorem
a²=b²+c² ⇒ a=√b²+c²
if b is 4 and c is 2 an a is the unknown
so a=√(4)²+(2)²
a=√20
then get the rule of the area of the square
Area of the square= s²
s=a=√20 (a is the hypotenuse of the triangle and also a side in the square)
so s²=20
Area of the square=20 units square
PLEASE HELP!! WILL GIVE BRAIN AND 5 STARS
Answers
Answer:
angle B is congruent to angle H
Step-by-step explanation:
This is the formation needed to prove angle angle side.
Choose the expression that represents a quadratic expression.
O 6x4 - 5x3 + 3x2 -7x - 8
) 5x3 + 3x2 -7x - 8
O 2x2 + 3x - 1
. 3x - 1
Answers
Answer:
3) 2[tex]x^{2}[/tex] + 3x - 1
Step-by-step explanation:
A quadratic expression is an expression involving a squared term
It can be written as y = a[tex]x^{2}[/tex] + bx + c, where a ≠ 0
// note that here b and c can be equal to 0
1) 6[tex]x^{4}[/tex] - 5[tex]x^{3}[/tex] + 3[tex]x^{2}[/tex] - 7x - 8 is simply incorrect because you can't write in the previously mentioned form. It is a quartic function, since the unknown variable x in forth degree. It can be written as y = a[tex]x^{4}[/tex] +b[tex]x^{3}[/tex] +c[tex]x^{2}[/tex] + dx + e, where a before [tex]x^{4}[/tex] ≠ 0
2) 5[tex]x^{3}[/tex] + 3[tex]x^{2}[/tex] - 7x - 8 is simply incorrect because you can't write in the previously mentioned form. It is a cubic function, since the unknown variable x in third degree.
3) 2[tex]x^{2}[/tex] + 3x - 1 is correct
4) 3x - 1 is incorrect because there is no squared term. You could also say that here a = 0 and write it as y = 0 * [tex]x^{2}[/tex] + 3x - 1. It is also called a linear function because if you'd draw a graph, it would be a line
Answer:
2x2 + 3x - 1
Step-by-step explanation:
if 3 boys build a snow manin 24 minutes how many can 9 finish building in 1 hour
Answers
Answer:
what does "manin" mean I can help i just need to know what that word means
i get ur question now! :)
so in 72 minutes 9 kids can make 8 snowman's
Hope this helps u and A LOT! :)
Step-by-step explanation:
Answer:
The answer is 6.
Find the shaded area
Answers
Answer:
area of big rectangle=l×b=12×18=216cm²
area of smaller square=l²=8²=64cm²
area of shaded area =area of (bigger rectangle-smaller square)=216-64=152cm²
WILL GIVE BRAINIEST!!! IF UR ANSWER IS RIGHT
Answers
Answer:
-1
Step-by-step explanation:
the slope of this one is y=x-21
in order for it to be perpendicular the sign changes and the slope flips
but because the slope is 1 you just change the slope to -1
A therm is a unit of heat. The hogans paid $.38 per therm of natural gas. In September they paid $19.57 for natural gas. How many therms did they use
Answers
Answer:
51.5 thermes of gas were used
