Hi.... I'll use the Quadratic Formula....
[tex]x^{2}=-5x-3\rightarrow x^{2}+5x+3=0\rightarrow x=\dfrac{-5\pm \sqrt{5^{2}-4\times 1\times3}}{2\times 1}\rightarrow\\ x=\dfrac{-5\pm\sqrt{13}}{2}\rightarrow \boxed{x_{1}=\dfrac{-5-\sqrt{13}}{2}}\quad \text{or}\quad \boxed{x_{2}=\dfrac{-5+\sqrt{13}}{2}}[/tex]
Thanks....
