Area of a trapezoid


This lesson will show how we find the area of a trapezoid by using the formula you see below the trapezoid



Area of a trapezoid formula
Example #1:

If b1 = 7 cm, b2 = 21 cm, and h = 2 cm, find A

(b1 + b2)/2 = (7 + 21)/2 = 28/2 = 14

A= 14 × 2 = 28 cm

Example #2:

If b1 = 15 cm, b2 = 25 cm, and h = 10 cm, find A

(b1 + b2)/2 = (15 + 25)/2 = 40/2 = 20

A= 20 × 10 = 200 cm

Example #3:

If b1 = 9 cm, b2 = 15 cm, and h = 2 cm, find A

(b1 + b2)/2 = (9 + 15)/2 = 24/2 = 12

A= 12 × 2 = 24 cm

Practice with this calculator Trapezoid calculator


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