$$x^{4}y^{6}z^{4}(3a+6b)-15xy^{4}z^{2}(a+2b)^{3}$$
$3x\left(a+2b\right)z^{2}y^{4}\left(x^{3}\left(yz\right)^{2}-5\left(a+2b\right)^{2}\right)$
$6by^{6}\left(xz\right)^{4}+3ay^{6}\left(xz\right)^{4}-120xz^{2}b^{3}y^{4}-15xz^{2}a^{3}y^{4}-180axy^{4}\left(bz\right)^{2}-90bxy^{4}\left(az\right)^{2}$
