$x^{2}-3x-10=0$
Solve with the quadratic formula$x_{1,2}=\frac{-(-3)\pm \sqrt{(-3)^{2}-4\cdot 1\cdot (-10)}}{2\cdot 1}$
$\sqrt{(-3)^{2}-4\cdot 1\cdot (-10)}=7$$x_{1,2}=\frac{-(-3)\pm 7}{2\cdot 1}$
Separate the solutions$x_{1}=\frac{-(-3)+7}{2\cdot 1},x_{2}=\frac{-(-3)-7}{2\cdot 1}$
$x=\frac{-(-3)+7}{2\cdot 1}:{\quad}5$$=5$
$x=\frac{-(-3)-7}{2\cdot 1}:{\quad}-2$$=-2$
The solutions to the quadratic equation are:$x=5,x=-2$