Question

Factorise: $49x^2-\frac{16}{25}$

Answer 1

Given expression is $49x^2-\frac{16}{25}$

We will use identity $a^2-b^2=(a-b)(a+b)$

We have $49x^2-\frac{16}{25}=(7x{)}^2-{\left(\frac{4}{5}\right)}^2$

$=(7x+\frac{4}{5})(7x-\frac{4}{5})$