Hello :
<span>4x-5y=13...(1)
x+5y=-3...(2)
(1)+(2) : 5x = 10
x=2
subsct in (2) : 2+5y = -3
5y =-5
y = -1
</span>
Simple, what you're basically doing is simplifying,

well, you have 3x and you have

12/3=4
and you can "cancel" out an x, making your answer,

.
Answer:
c because if you subtract