Question

SOMEONE HELP PLEASE QUICK!!

For the following system, if you isolated x in the second equation to use the Substitution Method, what expression would you substitute into the first equation?

3x + y = 8
−x − 2y = −10

A. −2y + 10
B. 2y + 10
C. 2y − 10
D. −2y − 10

Answer 1

The original equation we have is : −x − 2y = −10

We need to isolate the x, which means that we need to get x alone on one side of the equation preferably in a positive form.

So, going back to the original expression:

−x − 2y = −10

To make x positive, we will add x to both sides of the equation, thus, we get:

-2y = -10 + x

The next step is to eliminate the -10 from beside the x. To do this we will add 10 to both sides of the equation. When doing this we get:

x = -2y + 10

The answer is A. -2y + 10