Solve x^2+4=64

$$x ^ { 2 } + 4 = 64$$

Solve for x

$$x=2\sqrt{15}\approx 7.745966692$$

$$x=-2\sqrt{15}\approx -7.745966692$$

Steps by Finding Square Root

Subtract 4 from both sides.

$$x^{2}=64-4$$

Subtract 4 from 64 to get 60.

$$x^{2}=60$$

Take the square root of both sides of the equation.

$$x=2\sqrt{15} x=-2\sqrt{15}$$

Steps Using the Quadratic Formula

Subtract 64 from both sides.

$$x^{2}+4-64=0$$

Subtract 64 from 4 to get -60.

$$x^{2}-60=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -60 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{0±\sqrt{0^{2}-4\left(-60\right)}}{2}$$

Square 0.

$$x=\frac{0±\sqrt{-4\left(-60\right)}}{2}$$

Multiply -4 times -60.

$$x=\frac{0±\sqrt{240}}{2}$$

Take the square root of 240.

$$x=\frac{0±4\sqrt{15}}{2}$$

Now solve the equation x=\frac{0±4\sqrt{15}}{2} when ± is plus.

$$x=2\sqrt{15}$$

Now solve the equation x=\frac{0±4\sqrt{15}}{2} when ± is minus.

$$x=-2\sqrt{15}$$

The equation is now solved.

$$x=2\sqrt{15} x=-2\sqrt{15}$$