Solve u^2=5

$$u ^ { 2 } = 5$$

Solve for u

$$u=\sqrt{5}\approx 2.236067977$$

$$u=-\sqrt{5}\approx -2.236067977$$

Steps by Finding Square Root

Take the square root of both sides of the equation.

$$u=\sqrt{5} u=-\sqrt{5}$$

Steps Using the Quadratic Formula

Subtract 5 from both sides.

$$u^{2}-5=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -5 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$u=\frac{0±\sqrt{0^{2}-4\left(-5\right)}}{2}$$

Square 0.

$$u=\frac{0±\sqrt{-4\left(-5\right)}}{2}$$

Multiply -4 times -5.

$$u=\frac{0±\sqrt{20}}{2}$$

Take the square root of 20.

$$u=\frac{0±2\sqrt{5}}{2}$$

Now solve the equation u=\frac{0±2\sqrt{5}}{2} when ± is plus.

$$u=\sqrt{5}$$

Now solve the equation u=\frac{0±2\sqrt{5}}{2} when ± is minus.

$$u=-\sqrt{5}$$

The equation is now solved.

$$u=\sqrt{5} u=-\sqrt{5}$$