# How can you evaluate ((2x-5)(x-y)) / ((y-x)(3x-1))?

Jul 29, 2015

$- \frac{2 x - 5}{3 x - 1}$

#### Explanation:

First note that:
$\frac{\left(2 x - 5\right) \left(x - y\right)}{\left(y - x\right) \left(3 x - 1\right)} = - \frac{\left(2 x - 5\right) \cancel{\left(x - y\right)}}{\cancel{\left(x - y\right)} \left(3 x - 1\right)}$

So in fact this expression is only a function of $x$ and the value of $y$ is irrelevant. Plug the value of $x$ into the remaining expression to evaluate it, for example $x = 1$:

$- \frac{2 x - 5}{3 x - 1} = - \frac{2 - 5}{3 - 1} = - \frac{- 3}{2} = \frac{3}{2}$