Solve x^2+7*12=0

$$x ^ { 2 } + 7 \times 12 = 0$$

Solve for x (complex solution)

$$x=-2\sqrt{21}i\approx -0-9.16515139i$$

$$x=2\sqrt{21}i\approx 9.16515139i$$

Steps by Finding Square Root

Multiply 7 and 12 to get 84.

$$x^{2}+84=0$$

Subtract 84 from both sides. Anything subtracted from zero gives its negation.

$$x^{2}=-84$$

The equation is now solved.

$$x=2\sqrt{21}i x=-2\sqrt{21}i$$

Steps Using the Quadratic Formula

Multiply 7 and 12 to get 84.

$$x^{2}+84=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and 84 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{0±\sqrt{0^{2}-4\times 84}}{2}$$

Square 0.

$$x=\frac{0±\sqrt{-4\times 84}}{2}$$

Multiply -4 times 84.

$$x=\frac{0±\sqrt{-336}}{2}$$

Take the square root of -336.

$$x=\frac{0±4\sqrt{21}i}{2}$$

Now solve the equation x=\frac{0±4\sqrt{21}i}{2} when ± is plus.

$$x=2\sqrt{21}i$$

Now solve the equation x=\frac{0±4\sqrt{21}i}{2} when ± is minus.

$$x=-2\sqrt{21}i$$

The equation is now solved.

$$x=2\sqrt{21}i x=-2\sqrt{21}i$$