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?

2x + y = 9
−x − y = −8

−8 + y

−8 − y

8 + y

8 − y

Question

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?

2x + y = 9
−x − y = −8 

 −8 + y 

 −8 − y 

 8 + y 

 8 − y

angelwings996 · Answer

Okay, so you are solving for x in the second equation. You would add y to both sides which would give you -x = y - 8.

Now you need to divide both sides by -1 to get rid of the -x and you are left with x = -y + 8.