Answer
$3(m+5)(m^2-5m+25)$
Work Step by Step
RECALL:
$a^3+b^3 = (a+b)(a^2-ab+b^2)$
Factor out $3$ to have:
$=3(m^3+125)$
Write $125$ as a cube to have:
$=3(m^3+5^3)$
Factor the sum of two cubes using the formula above with $a=m$ and $b=5$ to have:
$=3(m+5)[m^2 - m(5) + 5^2]
\\=3(m+5)(m^2-5m+25)$
