Question

Simplify using suitable identity: (4√5 – 7) ².

please answer fast​

Answer 1

Answer:

$\bold{ \bold{ (4√5 – 7) ²}}$

$= ( {4 \sqrt{5} )}^{2} - 2 \times 4 \sqrt{5} \times 7 + {7}^{2}$

$= 16 \times 5 - 56\sqrt{5} + 49$

$= 80 - 56 \sqrt{5} + 49$

$= \boxed{\underline \bold{129 - 56 \sqrt{5} }}$

Identity used :—

$\large{ \boxed{ \mathtt{ \color{red}{ \bold {{(x - y)}^{2} = {x}^{2} - 2xy + {y}^{2} }}}}}$