Right Trapezoid

A trapezoid is a trapezoid with one right angle (90°). It is also termed as a right angle trapezoid. Since there is one right angle at one of its base, another right angled is automatically formed at the opposite base. So in other words, we can also say that a trapezoid with two right angles is a right trapezoid.

Properties

1. Has 2 adjacent right angles; ∠ABC and ∠DAB are 90°
2. Has all the other properties of a trapezoid

Formulas

Let us solve an example to understand the concept better.

Solved Example

Calculate the area of a right trapezoid with bases 21 cm and 15 cm and height 11 cm.

Solution:

As we know,
Area (A) = ½ (a + b) × h, here a = 21 cm, b = 15 cm, h = 11 cm
∴A = ½ (21 +15) ×11
= 198 cm²

E.g.1)