A trapezoid is a closed two-dimensional geometric figure having four linear sides, two of which are parallel. The parallel segments are referred to as bases while the other two sides are called legs. The altitude of the trapezoid pertains to the distance that forms a 90-degree angle between the bases.
Aside from the base, leg and altitude, a trapezoid is also characterized by its median, perimeter and area. A trapezoid's median refers to the connecting line between the midpoints of the non-parallel sides. Its perimeter measures the total distance around the figure. The formula for the perimeter is P = a + b + c + d, where "P" denotes the perimeter and "a," "b," "c" and "d" indicate the trapezoid's four sides. A trapezoid's area encompasses the entire space within the polygon. It can be calculated by using the formula A = <(b1 + b2)h>/2, where "A" denotes the area, "b1" and "b2" represent the two bases and "h" indicates the altitude.
A special type of trapezoid called an isosceles trapezoid, contains legs that are equidistant and equiangular from each base. A trapezoid that forms two right angles is known as a right trapezoid and a trapezoid with two pairs of parallel segments is called a parallelogram. A 4-sided polygon with no parallel sides is referred to as a trapezium.