# Pre-Algebra Examples

The area of a trapezoid is equal to times the height times the sum of the bases .

Substitute the values of the height and bases ( and ) into the formula for the area of a trapezoid.

Write as a fraction with denominator .

Factor out the greatest common factor .

Factor out of .

Factor out of .

Move .

Multiply by .

Cancel the common factor.

Rewrite the expression.

Multiply and .

Divide by .

Add and .

Multiply by .