$${ x }^{ 2 } -7 { x }^{ 2 } +2xy- { y }^{ 2 } +9$$
$9-y^{2}+2xy-6x^{2}$
$$-6x^{2}+2xy-y^{2}+9$$
Show Solution
Hide Solution
$2\left(y-6x\right)$
