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

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Answer 1 · 2017-07-11T16:53:01

See below.

Adding $8$ to both sides,

$x^2 + 2x + 21=0$

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

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

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