I'd start by finding the roots of the given expression. From these roots you can write the factors. -28 plus or minus sqrt(28^2 - 4(5)(-12) x = ------------------------------------------------------ 10 -28 plus or minus sqrt(784+240) = ----------------------------------------------- 10 -28 plus or minus 35 (approx) = --------------------------------------------- 10 35-28 -28-35 = ------------- and ------------ These roots are only approximate. However, 10 10 if we treat them as exact, with one root equal to 7/10 and the other -63 / 10
then the factors of the polynomial would be, approx., x-7/10 and x+63/10.
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