Factoring with a leading coefficient
3x^2+19x-72
Y = 3x^2 + 19x - 72 = 0
A*C = 3*(-72) = -216 = -8*27. Sum = 19
(3x^2-8x) + (27x-72) = 0
x(3x-8) + 9(3x-8) = 0
(3x-8)(x+9) = 0
3x-8 = 0
3x = 8
X = 8/3
x+9 = 0
X = -9
Solution: X = -9, and 8/3.