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What is the value of b? -11b + 7 =40 (also there is another question in the bottom of the picture. If you can answer it please do)

What is the value of b? -11b + 7 =40 (also there is another question in the bottom-example-1
User Potrzebie
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1 Answer

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Problem 1

The idea here is to follow PEMDAS in reverse to undo what is happening to the variable b, so we can isolate it.

-11b + 7 = 40

-11b = 40-7

-11b = 33

b = 33/(-11)

b = -3

To check this value, plug it back into the original equation. You should get 40 on each side to help confirm the answer.

Answer: b = -3

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Problem 2

There are two ways we can solve. One method is to use the hint your teacher gave you. So we'll distribute first and then follow the same idea as problem 1

9(p-4) = -18

9p-36 = -18

9p = -18+36

9p = 18

p = 18/9

p = 2

Another method you can use is to follow these steps

9(p-4) = -18

p-4 = -18/9

p-4 = -2

p = -2+4

p = 2

Either way, we get the same result. To check the answer, replace every p with 2 in the original equation. You should get -18 on the left side after simplifying.

Answer: p = 2

User Dlane
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