\[\frac{2}{\sqrt{5} + 3} = \frac{2\left( \sqrt{5} - 3 \right)}{\left( \sqrt{5} + 3 \right)\left( \sqrt{5} - 3 \right)} =\]
\[= \frac{2\left( \sqrt{5} - 3 \right)}{5 - 9} = \frac{2\left( \sqrt{5} - 3 \right)}{- 4} =\]
\[= - 0,5\left( \sqrt{5} - 3 \right) = 1,5 - 0,5\sqrt{5}.\]