Question

15. If xy = 20 and (x + y)2 = 70, then x2 + y2 is equal to​

Answer 1

Step-by-step explanation:

given that

xy = 20 and (x+y)^2= 70

Since

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

=(70)-2×20

=70-40

=30

Hence x^2+y^2=30 Answer