Question

I keep messing this up for #13 I got (1/19, 35/38) and for #15 I got (2,-1) both of which I know are wrong, someone help me understand what I did wrong?

Answer 1

2x  + y = x/2 + 1  multiply  this by -4:-
-8x - 4y = -2x - 4
4y         = 2x       Adding:-

-8x = -4
x = 1/2

Substitute in 4y = 2x:-

4y = 2*1/2

y = 1/4 

Answer ( 1/2, 1/4)