How do you solve x^2 + 2x + 13 = -8?

1 Answer
Jul 11, 2017

See below.

Explanation:

Adding 8 to both sides,

x^2 + 2x + 21=0

Let's use the quadratic formula, as factoring will not work in this case.

x=\frac(-2\pm\sqrt(2^2-4(1)(21)))(2)=\frac(-2\pm\sqrt(-80))(2)=\frac(-2\pm4\sqrt(-5))(2)=\frac(-2\pm4i\sqrt(5))(2)=-1\pm2i\sqrt5