## Algebra 1

$-5-2\sqrt{5}$
Multiply using the conjugate. Remember that $(a^2-b^2)$ is $(a+b)(a-b)$ $\frac{\sqrt{5}}{2-\sqrt{5}}\cdot \frac{2+\sqrt{5}}{2+\sqrt{5}}=\frac{2\sqrt{5}+5}{4-5}=\frac{2\sqrt{5}+5}{-1}=-5-2\sqrt{5}$