{(x-y)(x+y)=12 {x+y=3(x-y)

Question

{(x-y)(x+y)=12

{x+y=3(x-y)

Answer 1

3(x-y)^2=12

x-y= +-2

x=+-2 +y

x1 = 2+y

2(2+2y)=12

2+2y=6

1+y=3

y1=2

x2=-2+y

-2(-2+2y)=12

-2+2y=-6

-1+y=-3

y2=-2

Ответ x1=4, y1 = 2, x2=-4, y2=-2