positive root of the equation $x^2+x-3-\sqrt{3}=0$ $x^2+x-3-\sqrt{3}=0$
using the quadratic formula we get 
$$x=\frac{-1+\sqrt{13+4\sqrt{3}}}{2}$$ for the positive root
but the actual answer is simply   $x=\sqrt3$
I am unable to perform the simplification any help would we helpful

Note that $(1+ 2 \sqrt3)^2 = 1 + 4 \sqrt 3 + 4 \cdot \sqrt 3^2 = 13 + 4 \sqrt 3$. The expression is now easy to simplify.
