x = 20
x = 15
x = 10
100x^2 + 400 = 0
9x^2 = 900
x = 2
NTS
x = 7
x = -5
x^2 - 15x = 100
x = -10
x^2 - 2x - 195 = 0
12x^2 - 24x = 0
x = 6
x = - 20
x^2 + 14x - 120 = 0
x = -7
5x^2 - 245 = 0
x = 0
x = - 13
x^2 + 28x + 196 = 0
x = - 14
