Question

If x² + y² = 60 and xy = 2 , find
i) x + y
ii)x - y

Answer 1

1. (x+y)^2=x^2+2xy+y^2
=(x^2+y^2) + 2xy
=60+2*2
=60+4
=64
so, x+y=√64
=8


2. (x-y)^2= x^2-2xy+y^2
=(x^2+y^2) -2xy
=60-2*2
=60-4
=56
so, x-y=√56

Answer 2

It is the right answer.