Evaluate -5+2x^2=-6x

$- 5 + 2 x^{2} = - 6 x$

Add $6 x$ to both sides of the equation.

$- 5 + 2 x^{2} + 6 x = 0$

Use the quadratic formula to find the solutions.

$\frac{- b \pm \sqrt{b^{2} - 4 (a c)}}{2 a}$

Substitute the values $a = 2$ , $b = 6$ , and $c = - 5$ into the quadratic formula and solve for $x$ .

$\frac{- 6 \pm \sqrt{6^{2} - 4 \cdot (2 \cdot - 5)}}{2 \cdot 2}$

Simplify.

Simplify the numerator.

Raise $6$ to the power of $2$ .

$x = \frac{- 6 \pm \sqrt{36 - 4 \cdot 2 \cdot - 5}}{2 \cdot 2}$

Multiply $- 4$ by $2$ .

$x = \frac{- 6 \pm \sqrt{36 - 8 \cdot - 5}}{2 \cdot 2}$

Multiply $- 8$ by $- 5$ .

$x = \frac{- 6 \pm \sqrt{36 + 40}}{2 \cdot 2}$

Add $36$ and $40$ .

$x = \frac{- 6 \pm \sqrt{76}}{2 \cdot 2}$

Rewrite $76$ as $2^{2} \cdot 19$ .

Factor $4$ out of $76$ .

$x = \frac{- 6 \pm \sqrt{4 (19)}}{2 \cdot 2}$

Rewrite $4$ as $2^{2}$ .

$x = \frac{- 6 \pm \sqrt{2^{2} \cdot 19}}{2 \cdot 2}$

Pull terms out from under the radical.

$x = \frac{- 6 \pm 2 \sqrt{19}}{2 \cdot 2}$

Multiply $2$ by $2$ .

$x = \frac{- 6 \pm 2 \sqrt{19}}{4}$

Simplify $\frac{- 6 \pm 2 \sqrt{19}}{4}$ .

$x = \frac{- 3 \pm \sqrt{19}}{2}$

Simplify the expression to solve for the $+$ portion of the $\pm$ .

Simplify the numerator.

Raise $6$ to the power of $2$ .

$x = \frac{- 6 \pm \sqrt{36 - 4 \cdot 2 \cdot - 5}}{2 \cdot 2}$

Multiply $- 4$ by $2$ .

$x = \frac{- 6 \pm \sqrt{36 - 8 \cdot - 5}}{2 \cdot 2}$

Multiply $- 8$ by $- 5$ .

$x = \frac{- 6 \pm \sqrt{36 + 40}}{2 \cdot 2}$

Add $36$ and $40$ .

$x = \frac{- 6 \pm \sqrt{76}}{2 \cdot 2}$

Rewrite $76$ as $2^{2} \cdot 19$ .

Factor $4$ out of $76$ .

$x = \frac{- 6 \pm \sqrt{4 (19)}}{2 \cdot 2}$

Rewrite $4$ as $2^{2}$ .

$x = \frac{- 6 \pm \sqrt{2^{2} \cdot 19}}{2 \cdot 2}$

Pull terms out from under the radical.

$x = \frac{- 6 \pm 2 \sqrt{19}}{2 \cdot 2}$

Multiply $2$ by $2$ .

$x = \frac{- 6 \pm 2 \sqrt{19}}{4}$

Simplify $\frac{- 6 \pm 2 \sqrt{19}}{4}$ .

$x = \frac{- 3 \pm \sqrt{19}}{2}$

Change the $\pm$ to $+$ .

$x = \frac{- 3 + \sqrt{19}}{2}$

Rewrite $- 3$ as $- 1 (3)$ .

$x = \frac{- 1 \cdot 3 + \sqrt{19}}{2}$

Factor $- 1$ out of $\sqrt{19}$ .

$x = \frac{- 1 \cdot 3 - 1 (- \sqrt{19})}{2}$

Factor $- 1$ out of $- 1 (3) - 1 (- \sqrt{19})$ .

$x = \frac{- 1 (3 - \sqrt{19})}{2}$

Move the negative in front of the fraction.

$x = - \frac{3 - \sqrt{19}}{2}$

Simplify the expression to solve for the $-$ portion of the $\pm$ .

Simplify the numerator.

Raise $6$ to the power of $2$ .

$x = \frac{- 6 \pm \sqrt{36 - 4 \cdot 2 \cdot - 5}}{2 \cdot 2}$

Multiply $- 4$ by $2$ .

$x = \frac{- 6 \pm \sqrt{36 - 8 \cdot - 5}}{2 \cdot 2}$

Multiply $- 8$ by $- 5$ .

$x = \frac{- 6 \pm \sqrt{36 + 40}}{2 \cdot 2}$

Add $36$ and $40$ .

$x = \frac{- 6 \pm \sqrt{76}}{2 \cdot 2}$

Rewrite $76$ as $2^{2} \cdot 19$ .

Factor $4$ out of $76$ .

$x = \frac{- 6 \pm \sqrt{4 (19)}}{2 \cdot 2}$

Rewrite $4$ as $2^{2}$ .

$x = \frac{- 6 \pm \sqrt{2^{2} \cdot 19}}{2 \cdot 2}$

Pull terms out from under the radical.

$x = \frac{- 6 \pm 2 \sqrt{19}}{2 \cdot 2}$

Multiply $2$ by $2$ .

$x = \frac{- 6 \pm 2 \sqrt{19}}{4}$

Simplify $\frac{- 6 \pm 2 \sqrt{19}}{4}$ .

$x = \frac{- 3 \pm \sqrt{19}}{2}$

Change the $\pm$ to $-$ .

$x = \frac{- 3 - \sqrt{19}}{2}$

Rewrite $- 3$ as $- 1 (3)$ .

$x = \frac{- 1 \cdot 3 - \sqrt{19}}{2}$

Factor $- 1$ out of $- \sqrt{19}$ .

$x = \frac{- 1 \cdot 3 - (\sqrt{19})}{2}$

Factor $- 1$ out of $- 1 (3) - (\sqrt{19})$ .

$x = \frac{- 1 (3 + \sqrt{19})}{2}$

Move the negative in front of the fraction.

$x = - \frac{3 + \sqrt{19}}{2}$

The final answer is the combination of both solutions.

$x = - \frac{3 - \sqrt{19}}{2}, - \frac{3 + \sqrt{19}}{2}$

The result can be shown in multiple forms.

Exact Form:

$x = - \frac{3 - \sqrt{19}}{2}, - \frac{3 + \sqrt{19}}{2}$

Decimal Form:

$x = 0.67944947 \dots, - 3.67944947 \dots$

Evaluate -5+2x^2=-6x

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