(a−b)x+(a+b)y=a2−2ab−b2 ....(1)
(a+b)(x+y)=a2+b2
(a+b)x+(a+b)y=a2+b2 .....(2)
Subtracting equation (2) from (1), we obtain
(a−b)x−(a+b)x=(a2−2ab−b2)−(a2+b2)
(a−b−a−b)x=−2ab−2b2
−2bx=−2b(a+b)
x=a+b
Using equation (1), we obtain
(a−b)(a+b)+(a+b)y=a2−2ab−b2
a2−b2+(a+b)y=a2−2ab−b2
(a+b)y=−2ab
y=−2aba+b