Question

x menos y = 6 x + y=-7

Answer 1

{ x - y = 6
{ x + y = -7
----------------(+)
2x= - 1

x= -1 /2

x - y = 6

-1/2 - y = 6

-y = 6 + 1/2

y= -6 - 1/2

y = - 13/2