Question

If
x + 2y = 1
X– 2y = 13
then y =

Answer 1

y = -3

Explanation:

x + 2y = 1 then x = 1 - 2y

x– 2y = 13

substitute for x:

1 - 2y - 2y = 13

simplify:

-4y = 12

y = -3

x = 7