Question

If x2 + y2 = 9 and xy = 8, then x + y is equal to

Answer 1

(x+y)²=x²+y²+2xy

=9+16=(x+y)²

=(x+y)²=25

=x+y=5

hope this supports you

Answer 2

Answer:

(x+y)^2=x^2+y^2+2xy

or,(x+y)^2=9+2*8

or,(x+y)^2=25

or,(x+y)=5