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2x2 + 3x - 20 = 0
(2x - 5)(x + 4) = 0
2x - 5 = 0 x + 4 = 0
2x = 5 x = -4
x = 5/2
x = 5/2 & -4
2x2 + 3x - 20 = 0
(2x - 5)(x + 4) = 0
2x - 5 = 0 x + 4 = 0
2x = 5 x = -4
x = 5/2
x = 5/2 & -4