Question

Qual e o valor de x e y,-6x+2y=12 e 6x-y=-18?

Answer 1

-6x+2y=12(:2)
 6x-y=-18

-3x+y=6
 6x-y=-18
    3x = - 12 ==> x = - 4

y = 6 + 3x ==> y = 6+3.4 ==> y = 6+12 ==> y = 18