Answer
$3m(2m-5)$
Work Step by Step
Find the greatest common factor. Find the factors of each term and multiply the factors that are common to all the terms.
$6m^2=\underline3\times2\times\underline m\times m$
$15m=5\times\underline3\times\underline m$
GCF=$3\times m=3m$
Factor the GCF out of each term.
$6m^2-15m=3m(2m-5)$
