Solve -x^2=49

$$- x ^ { 2 } = 49$$

Solve for x (complex solution)

$$x=-7i$$

$$x=7i$$

Steps by Finding Square Root

Divide both sides by -1.

$$x^{2}=-49$$

The equation is now solved.

$$x=7i x=-7i$$

Steps Using the Quadratic Formula

Subtract 49 from both sides.

$$-x^{2}-49=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 0 for b, and -49 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{0±\sqrt{0^{2}-4\left(-1\right)\left(-49\right)}}{2\left(-1\right)}$$

Square 0.

$$x=\frac{0±\sqrt{-4\left(-1\right)\left(-49\right)}}{2\left(-1\right)}$$

Multiply -4 times -1.

$$x=\frac{0±\sqrt{4\left(-49\right)}}{2\left(-1\right)}$$

Multiply 4 times -49.

$$x=\frac{0±\sqrt{-196}}{2\left(-1\right)}$$

Take the square root of -196.

$$x=\frac{0±14i}{2\left(-1\right)}$$

Multiply 2 times -1.

$$x=\frac{0±14i}{-2}$$

Now solve the equation x=\frac{0±14i}{-2} when ± is plus.

$$x=-7i$$

Now solve the equation x=\frac{0±14i}{-2} when ± is minus.

$$x=7i$$

The equation is now solved.

$$x=-7i x=7i$$