Question

factorise 4x square + 9 y square + 16 z square + 12 x y - 24 y square minus 16 x square

Answer 1

correction, i think your question is
$4 {x}^{2} + 9 {y}^{2} + 16 {z}^{2} + 12xy - 24yz - 16zx$
factors:
${(2x + 3y - 4z)}^{2}$
that is
$(2x + 3y - 4z)(2x + 3y - 4z)$