What adds up to 11 and multiplies to 24?

x + y = 11

xy = 24

y = 11-x

xy = x (11-x) = 24

11x - x^2 = 24

x^2-11x + 24 = 0

(x-8)(x-3) = 0

x = 8 or 3

xy = 24; y =3 or 8

Answer 8 and 3