Pierre correctly simplified an expression. When he substituted x = 2 into the simplified expression, the value was 20. Which could be Pierre’s original expression?

a) 2(7x-4)

Explanation:

Let us first simplify these expressions by multiplying them:

a) 2(7x-4) = 14x-8

b) 2(x-19) = 2x-38

c) 2(x+10) = 2x+20

d) 2(5x+1) = 10x+2

Now, we just plug in x=2 into these simplified expressions:

a) 14x-8 = 28-8 = 20

b) 2x-38 = 4-38 = -34

c) 2x+20 = 4+20 = 24

d) 10x+2 = 20+2 = 22

Now, we see that the original expression was 2(7x-4).

answer: c

explanation:

there is a sequence and logical steps to give an answer of a trouble.

1) strategy is necessary to develop an project idea.

2) to study and know the environment where you are going to work ( ecosystem).

3)   the materials resources to built the ideas.

4) to give a priority order in the context that you study. in this case human needs.