Question

Evaluate the following using identities.
$9.2\times 8.8$.

Answer 1

$9.2\times 8.8$

$\Rightarrow (9+0.2)(9-0.2)$

$\Rightarrow (9{)}^2-(0.2{)}^2$ $\left[\right(a+b\left)\right(a-b)=a^2-b^2]$

$\Rightarrow 81-0.04$

$\Rightarrow 80.96$.