How do you solve $x (x + 2) = - 9$ $x( x + 2) = - 9$ ?

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Answer 1 · 2017-07-22T04:24:58

All you need to do is to get the quadratic formula:
$- b \pm \frac{\sqrt{b^{2} - 4 a c}}{2 a}$ $-b+-sqrt(b^2-4ac)/(2a)$
and plug the values in as is.

$x (x + 2) = - 9$ $x(x+2)=-9$

Use the order of operations to simplify and combine the equation into one polynomial $a x^{2} + b x + c$ $ax^2+bx+c$ .

$x^{2} + 2 x + 9 = 0$ $x^2+2x+9=0$

Plug the values in the quadratic formula as shown in the polynomial.

$- 2 \pm \frac{\sqrt{2^{2} - 4 (1) (9)}}{2 (1)}$ $-2+-sqrt(2^2-4(1)(9))/(2(1))$

Simplify the equation into its solutions.

$= \frac{- 2 \pm \sqrt{4} - 36}{2}$ $=(-2+-sqrt4-36)/2$
$= \frac{- 2 \pm 4 i \sqrt{2}}{2}$ $=(-2+-4isqrt2)/2$
$= - 1 \pm 2 i \sqrt{2}$ $=-1+-2isqrt2$

How do you solve x( x + 2) = - 9x(x+2)=−9x( x + 2) = - 9?