Solve 0=s(s+2)

$$0 = s ( s + 2 )$$

Solve for s

$$s=-2$$

$$s=0$$

Steps Using Factoring

Use the distributive property to multiply s by s+2.

$$0=s^{2}+2s$$

Swap sides so that all variable terms are on the left hand side.

$$s^{2}+2s=0$$

Factor out s.

$$s\left(s+2\right)=0$$

To find equation solutions, solve s=0 and s+2=0.

$$s=0 s=-2$$

Steps Using the Quadratic Formula

Use the distributive property to multiply s by s+2.

$$0=s^{2}+2s$$

Swap sides so that all variable terms are on the left hand side.

$$s^{2}+2s=0$$

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

$$s=\frac{-2±\sqrt{2^{2}}}{2}$$

Take the square root of 2^{2}.

$$s=\frac{-2±2}{2}$$

Now solve the equation s=\frac{-2±2}{2} when ± is plus. Add -2 to 2.

$$s=\frac{0}{2}$$

Divide 0 by 2.

$$s=0$$

Now solve the equation s=\frac{-2±2}{2} when ± is minus. Subtract 2 from -2.

$$s=-\frac{4}{2}$$

Divide -4 by 2.

$$s=-2$$

The equation is now solved.

$$s=0 s=-2$$

Steps for Completing the Square

Use the distributive property to multiply s by s+2.

$$0=s^{2}+2s$$

Swap sides so that all variable terms are on the left hand side.

$$s^{2}+2s=0$$

Divide 2, the coefficient of the x term, by 2 to get 1. Then add the square of 1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.

$$s^{2}+2s+1^{2}=1^{2}$$

Square 1.

$$s^{2}+2s+1=1$$

Factor s^{2}+2s+1. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.

$$\left(s+1\right)^{2}=1$$

Take the square root of both sides of the equation.

$$\sqrt{\left(s+1\right)^{2}}=\sqrt{1}$$

Simplify.

$$s+1=1 s+1=-1$$

Subtract 1 from both sides of the equation.

$$s=0 s=-2$$