Question

Factorise x^2-y^2/100

Answer 1

The equation is the following
$x^2- \frac{y^2}{100}$

This is a difference of two squares, the first one being the square of $x$, the second one being the square of $\frac{y}{10}$. The difference of two squares can be factorized as
$A^2 - B^2 = (A+B)(A-B)$

If we apply this rule to our equation, we find
$x^2- \frac{y^2}{100}=(x+ \frac{y}{10})(x- \frac{y}{10})$