Solve the equation

$\displaystyle x^2+4x=3$

should I move the 3 to the left so that I can factor it or is there another way?!

Also how do I get from $\displaystyle 4n^2=-8n-1$ to $\displaystyle {\frac{-2-\sqrt{3}}{2},\frac{-2+\sqrt{3}}{2}}$

Thanks!!