The Lesson
A trapezoid is a four sided shape with one pair of opposite parallel sides.Dictionary Definition
The Oxford English Dictionary defines a rectangle as "a quadrilateral figure having only two sides parallel."Parts of a Trapezoid

The parallel sides of a trapezoid are called bases.

The other sides of a trapezoid are called legs or lateral sides.
Properties of Trapezoids

Only one pair of sides of a trapezoid is parallel.
The other pair of sides is not parallel.
The Perimeter of a Trapezoid
The perimeter of a trapezoid is given by the formula:In this formula, b_{1} and b_{2} are the lengths of the bases of the trapezoid and l_{1} and l_{2} are the lengths of the legs of the trapezoid.
The Area of a Trapezoid
The area of a trapezoid is given by the formula:In this formula, b_{1} and b_{2} are the lengths of the bases of the trapezoid and h is the height of the trapezoid.
Read more about how to find the area of a trapezoid