# Precalculus Examples

Solve by Completing the Square
Add to both sides of the equation.
To create a trinomial square on the left side of the equation, find a value that is equal to the square of half of , the coefficient of .
Add the term to each side of the equation.
Simplify the equation.
Simplify the right side.
Simplify each term.
Remove parentheses around .
One to any power is one.
Simplify each term.
Remove parentheses around .
One to any power is one.
Factor the perfect trinomial square into .
Solve the equation for .
Take the square root of each side of the equation to set up the solution for
Remove the perfect root factor under the radical to solve for .
Simplify the right side of the equation.
Rewrite as .
Pull terms out from under the radical, assuming positive real numbers.
The complete solution is the result of both the positive and negative portions of the solution.
First, use the positive value of the to find the first solution.
Move all terms not containing to the right side of the equation.
Subtract from both sides of the equation.