1 Move all terms to one side.
{x}^{2}+15x+45=0
x
2
+15x+45=0
2 Use the Quadratic Formula.
x=\frac{-15+3\sqrt{5}}{2},\frac{-15-3\sqrt{5}}{2}
x=
2
−15+3
5
,
2
−15−3
5
3 Simplify solutions.
x=-\frac{3(5-\sqrt{5})}{2},-\frac{3(5+\sqrt{5})}{2}
x=−
2
3(5−
5
)
,−
2
3(5+
5
)
