solve the system of equations algebraically for real values of x and y
{ x + y = 16
x^2 + y^2 = 128
a. (6,6)
b. (8,6)
c. (9,8)
d. (8,8)
e. no solution
substitute for y and you have
x^2 + (16-x^2) = 128
Now just solve for x, and then get y.