2x-y=-5

-2x-5y=11

Eq1: 2x - y = -5

Eq2: -2x - 5y = 11

Add the 2 Eqs and get:
-6y = 6,
Divide both sides by -6:
y = 6 / -6 = -1.

Substitute -1 for y in Eq1:
2x - (-1) = -5,
2x + 1 = -5,
2x = -5 -1,
2x = -6,
Divide both sides by 2:
x = -6 / 2 = -3.

Solution set: (-3 , -1).