5. Finding area of trapezoids

• A *trapezoid* is a 4-sided polygon with exactly one pair of parallel sides. Rectangles and parallelograms are not trapezoids, since both pairs of opposite sides of a rectangle or parallelogram are parallel.

• The *bases of a trapezoid* are its parallel sides. The *height* of a trapezoid is the distance between the bases, measured along a line that is perpendicular to both bases.

• The area formula for a trapezoid is similar to the area formula for a rectangle or parallelogram. Instead of multiplying height by base to figure out area, multiply the trapezoid's height by the *average *of its two bases. In other words

• For each trapezoid in the figure at the right, count squares to find

- the bottom base b
_{1} - the top base b
_{2} - the height h

• Type the values of b

• Click on 'Check your work' at any time.

• When your score is perfect, click on 'New Quiz' to get new trapezoids.