Question

what must be added 4x+12x+5 to make it a
perfect square​

Answer 1

Answer:

4must be add I hope it will help you

Answer 2

$\large{\underline{\red{\mathfrak{Given \: equation:}}}}$

$\large{\sf{4 {x}^{2} + 12x \: + 5}}$

$\left\large{\sf{=4[ {x}^{2} + 3x \: + \frac{5}{4}] }}$

$\left\large{\sf{=4[ {x} +( { \frac{3}{2} )}^{2} \: - { (\frac{3}{2} )}^{2} + \frac{5}{4}] }}$

$\left\large{\sf{=4[ {x} +( { \frac{3}{2} )}^{2} \: - {4}] }}$

$\large{\sf{\pink{hence, \: 4 \: must \: be \: added \: to \: make \: perfect \: square}}}$