Originally Posted by

**bryang** I'm trying to simplify this complex fraction:

$\displaystyle \frac{1-\frac{x}{y}}{1-\frac{x^2}{y^2}}$

but I don't know what to do with the ones in front of the fractions. This is as far as I have gotten. The common denominator is $\displaystyle y^2$ so I need to multiply them by $\displaystyle y^2$, but how?

$\displaystyle \frac{(1-\frac{x}{y})\frac{y^2}{1}}{(1-\frac{x^2}{y^2})\frac{y^2}{1}}$

These are mixed numbers right? To multiply a mixed number by a fraction, you need to change the mixed number to an improper fraction, but how do I do it when I don't know how much x and y are worth?