Real numbers x and y satisfy
x + xy = 250y
x - xy = -240y
Enter all possible values of x, separated by commas.
Add the equations and we get that
2x = 10y
x = (10/2) y = 5y
Sub this into the first equation for x
5y + (5y)y = 250 y
5y = 250y - 5y
5y^2 - 245y = 0
5y ( y - 49) = 0
5y = 0 y - 49 = 0
x = 5(0) = 0 y = 49
x = 5(49) = 245
x = 0, 245