x2 + 9x + 20 = 0
x2 + 5x - 24 = 0
x2 + 5x - 50 = 0
x2 - 7x + 10 = 0
x2 - 15x + 50 = 0
x2 + 11x + 30 = 0
x2 + 4x + 4 = 0
x2 + 2x - 15 = 0
