Solve x^2=-16

$$x ^ { 2 } = - 16$$

Solve for x (complex solution)

$$x=-4i$$

$$x=4i$$

Steps by Finding Square Root

The equation is now solved.

$$x=4i x=-4i$$

Steps Using the Quadratic Formula

Add 16 to both sides.

$$x^{2}+16=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and 16 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{0±\sqrt{0^{2}-4\times 16}}{2}$$

Square 0.

$$x=\frac{0±\sqrt{-4\times 16}}{2}$$

Multiply -4 times 16.

$$x=\frac{0±\sqrt{-64}}{2}$$

Take the square root of -64.

$$x=\frac{0±8i}{2}$$

Now solve the equation x=\frac{0±8i}{2} when ± is plus.

$$x=4i$$

Now solve the equation x=\frac{0±8i}{2} when ± is minus.

$$x=-4i$$

The equation is now solved.

$$x=4i x=-4i$$