If x + y = -5 and xy = 3, then what is x2+y2?
Solving for x and y, we get x and y are equal to -5/2 + sqrt(37)/2 and -5/2 - sqrt(37)/2 in some order.
Therefore, x^2 + y^2 = (-5/2 + sqrt(37)/2)^2 + (-5/2 - sqrt(37)/2)^2 = 31.
