Answer:
y = -0.5
Step-by-step explanation:
given
5x – 7y = 7 ------- eq 1
y = -5x + 3 (we rearrange this so that the terms are in the same order as eq 1)
-5x – y = -3 ----- eq 2
by elimination, eq 1 + eq 2
(5x – 7y) + (-5x – y) = 7 + (-3)
5x - 7y -5x - y = 7-3
-8y = 4
y = 4/(-8)
y = -0.5