Question

For the following system, if you isolated x in the first equation to use the Substitution Method, what expression would you substitute into the second equation? −x − 2y = −4 and 3x + y = 12

A.) −2y − 4

B.) 2y − 4

C.) 2y + 4

D.) -2y + 4

Answer 1

-x - 2y = -4

Isolate x:

-2y = -4 + x (add x to both sides)

-2y + 4 = x (add 4 to both sides)

The answer is D