Question 887872
x +y = 210
y = x^2
substitute for y in first equation
x^2 +x -210 = 0
factor equation
(x+15)*(x-14) = 0
x = -15 or 14
y = 225 or 196
solution1 is x = -15, y = 225
solution2 is x =  14, y = 196