take 5x as a factor of each term
5x(x^2 -4x - 12)
you now need to factor the quadratic...
hope it helps
To factor the expression 5 x 3 − 20 x 2 − 60 x , first factor out the GCF, which is 5 x , yielding 5 x ( x 2 − 4 x − 12 ) . Then, factor the quadratic to get 5 x ( x − 6 ) ( x + 2 ) . This results in the completely factored form 5 x ( x − 6 ) ( x + 2 ) .
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