$$( g ) ( 2 a - 3 b ) ^ { 2 } - ( 3 a - 2 b ) ^ { 2 }$$
$9gb^{2}+4ga^{2}-4b^{2}+12ab-12abg-9a^{2}$
$g\left(2a-3b\right)^{2}-\left(3a-2b\right)^{2}$
