Solve -99=7*-x^2-4-3

$$-99=7 \times - { x }^{ 2 } -4-3$$

Solve for x

$$x = \frac{2 \sqrt{161}}{7} \approx 3.625307869$$

$$x = -\frac{2 \sqrt{161}}{7} \approx -3.625307869$$

Steps by Finding Square Root

Subtract 3 from -4 to get -7.

$$-99=7\left(-x^{2}\right)-7$$

Swap sides so that all variable terms are on the left hand side.

$$7\left(-x^{2}\right)-7=-99$$

Add 7 to both sides.

$$7\left(-x^{2}\right)=-99+7$$

Add -99 and 7 to get -92.

$$7\left(-x^{2}\right)=-92$$

Divide both sides by 7.

$$-x^{2}=-\frac{92}{7}$$

Divide both sides by -1.

$$x^{2}=\frac{-\frac{92}{7}}{-1}$$

Express \frac{-\frac{92}{7}}{-1} as a single fraction.

$$x^{2}=\frac{-92}{7\left(-1\right)}$$

Multiply 7 and -1 to get -7.

$$x^{2}=\frac{-92}{-7}$$

Fraction \frac{-92}{-7} can be simplified to \frac{92}{7} by removing the negative sign from both the numerator and the denominator.

$$x^{2}=\frac{92}{7}$$

Take the square root of both sides of the equation.

$$x=\frac{2\sqrt{161}}{7} x=-\frac{2\sqrt{161}}{7}$$

Steps Using the Quadratic Formula

Subtract 3 from -4 to get -7.

$$-99=7\left(-x^{2}\right)-7$$

Swap sides so that all variable terms are on the left hand side.

$$7\left(-x^{2}\right)-7=-99$$

Add 99 to both sides.

$$7\left(-x^{2}\right)-7+99=0$$

Add -7 and 99 to get 92.

$$7\left(-x^{2}\right)+92=0$$

Multiply 7 and -1 to get -7.

$$-7x^{2}+92=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute -7 for a, 0 for b, and 92 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{0±\sqrt{0^{2}-4\left(-7\right)\times 92}}{2\left(-7\right)}$$

Square 0.

$$x=\frac{0±\sqrt{-4\left(-7\right)\times 92}}{2\left(-7\right)}$$

Multiply -4 times -7.

$$x=\frac{0±\sqrt{28\times 92}}{2\left(-7\right)}$$

Multiply 28 times 92.

$$x=\frac{0±\sqrt{2576}}{2\left(-7\right)}$$

Take the square root of 2576.

$$x=\frac{0±4\sqrt{161}}{2\left(-7\right)}$$

Multiply 2 times -7.

$$x=\frac{0±4\sqrt{161}}{-14}$$

Now solve the equation x=\frac{0±4\sqrt{161}}{-14} when ± is plus.

$$x=-\frac{2\sqrt{161}}{7}$$

Now solve the equation x=\frac{0±4\sqrt{161}}{-14} when ± is minus.

$$x=\frac{2\sqrt{161}}{7}$$

The equation is now solved.

$$x=-\frac{2\sqrt{161}}{7} x=\frac{2\sqrt{161}}{7}$$