A trapezium ABCD has side AD parallel to BC. ∠BAD = 90°, BC = 3 cm and AD = 8 cm. If the perimeter of this trapezium is 36 cm, then its area, in sq. cm, is
Explanation:
Let AB = x
In right ∆CED,CE = AB = x ⇒ CD = x2+25
In the given figure, ⇒ 3 + 8 + x + x2+25 = 36 ⇒ x2+25 = 25 – x ⇒ x2 + 25 = 625 + x2 – 50x ⇒ 50x = 600 ⇒ x = 12
Now, area of a trapezium = 1/2 × (sum of parallel sides) × height = 1/2 × 11 × 12 = 66
Hence, 66.
Help us build a Free and Comprehensive Preparation portal for various competitive exams by providing us your valuable feedback about Apti4All and how it can be improved.