Question

Please help me for this question guys.
I definitely make u as brainliest.​

Answer 1

$we \: have$

$4x {}^{2} + 9y {}^{2} + 25z {}^{2} - 12xy - 30yz + 20zx$

$= (2x) {}^{2} + ( -3y) {}^{2} + (5z {}^{2} ) + 2(2x)( - 3y) + 2(3y)(5z) + 2(5z)(2x$

$(x + y + z) {}^{2} x {}^{2} + y {}^{2} + z {}^{2} + 2xy + 2yz + 2zx$

$compare \: with \: this \: identity \: we \: get$

$= (2x - 3y + 5z) {}^{2}$

$(2x - 3y + 5z)(2x - 3y + 5z)$

this is the answer of 1st question