Answer
$5(k^3+4k^2-3)$
Work Step by Step
Find the greatest common factor. Find the prime factors of each term and multiply the factors that are common to all the terms.
$5k^3=\underline 5\times k\times k\times k$
$20k^2=\underline 5\times2\times2\times k\times k$
$15=\underline 5\times3$
GCF $=5$
Factor the GCF out of each term. Use the factors from each term that are not part of the GCF.
$5k^3+20k^2-15=5(k^3+4k^2-3)$
