Question 430547

x-y = 1 , so x= y+1

substitute the value of x in 

x^2 -xy -y^2 =-5

=> (1+y)^2 -(1+y)y - y^2 = -5

=> 1 + y^2 +2y -y - y^2 -y^2 = -5

=> y^2 -y -6 = 0   

=> (y+2)(y-3) =0


y = -2 or y =3

when y = -2, x= -1

when y = 3 , x = 4