Answer:
7) A 8) C
Explanation:
number 7 tells us that y=x+1
so we just basically plug it in
2x+3(x+1)=4 Answer: A
to eliminate x's in number 8, we have to multiply one of the equations by -1
let's multiply the second one
4x+3y=6
4x ·-1-y·1=2·-1
4x+3y=6
-4x+y=-2
x's eliminate
4y=4, meaning that the answer is C