Question: Factorize:
$9 x^{2}+16 y^{2}+4 z^{2}-24 x y+16 y z-12 x z$
Solution:
We have :
$9 x^{2}+16 y^{2}+4 z^{2}-24 x y+16 y z-12 x z$
$=(-3 x)^{2}+(4 y)^{2}+(2 z)^{2}+2(-3 x)(4 y)+2(4 y)(2 z)+2(2 z)(-3 x)$
$=[(-3 x)+(4 y)+(2 z)]^{2}$
$=(-3 x+4 y+2 z)^{2}$
