www.khanacademy.org/math/basic-geo/basic-geo-area-and-perimeter/area-trap-composite/v/area-of-a-trapezoid-1

Area of a trapezoid is found with the formula, A=(a+b)/2 x h. Learn how to use the formula to find area of trapezoids.

www.mathgoodies.com/lessons/vol1/area_trapezoid.html

To find the area of a trapezoid, take the sum of its bases, multiply the sum by the height of the trapezoid, and then divide the result by 2, The formula for the area ...

www.virtualnerd.com/tutorials/?id=PreAlg_11_03_0004

www.mathopenref.com/trapezoidarea.html

Area of a trapezoid ("trapezium" in British usage). The number of square units it takes to completely fill a trapezoid. Formula: Average width × Altitude.

www.wikihow.com/Calculate-the-Area-of-a-Trapezoid

How to Calculate the Area of a Trapezoid. A trapezoid (also known as a trapezium in British English) is a quadrilateral with two parallel sides of different lengths.

keisan.casio.com/exec/system/1223273662

Calculates the area of a trapezoid given two parallel sides and the height.

illuminations.nctm.org/Lesson.aspx?id=1893

The main portion of this lesson involves the derivation of an area formula for trapezoids. Prior to that, allow students some exploration time. Ask them to suggest ...

www.mathwords.com/a/area_trapezoid.htm

Area of a Trapezoid. The formula is given below. See also. Trapezoid, bases of a trapezoid, altitude of a trapezoid. this page updated 21-feb-16. Mathwords: ...