Question

-2x - 5y = 13 2x - 5y =17

Answer 1

{-2x-5y=13

{2x-5y=17    (+)

  -2x+2x-5y-5y=13+17

-10y=30     /:(-10)

y=-3

2x-5y=17

2x-5*(-3)=17

2x+15=17

2x=2

x=1

Solution: (1; -3)