Question

Simplify:
$[{\left(5\right)}^2-{\left(\frac{1}{4}\right)}^{-2}]\times {\left(\frac{3}{4}\right)}^{-2}$

Answer 1

$\left[{\left(5\right)}^2-{\left(\frac{1}{4}\right)}^{-2}\right]\times {\left(\frac{3}{4}\right)}^{-2}$

$=\left[25-{\left(4\right)}^2\right]\times {\left(\frac{4}{3}\right)}^2$

$=\left(25-16\right)\times \frac{16}{9}$

$=9\times \frac{16}{9}=16$