Question

AND Is a trapezium in which ABBA is parallel to DR. diagonal AC and BD intersect each other at O. if AO/OC = BO/OD =1/2 and AB =4cm, find CD​

Answer 1

Answer:

Step-by-step explanation:

n figure, compute the area of quadrilateral ABCD.

Quadrilateral ABCD

Solution:

Given:

DC = 17 cm, AD = 9 cm and BC = 8 cm

In ΔBCD we have

CD2 = BD2 + BC2

⇒ 172 = BD2 + 82

⇒ BD2 = 289 − 64

⇒ BD = 15

In ΔABD we have

AB2 + AD2 = BD2

⇒ 152 = AB2 + 92

⇒ AB2 = 225 − 81 = 144

⇒ AB = 12

ar(quad ABCD) = ar(ΔABD) + ar(ΔBCD)

ar(quad ABCD) = 1/2(12 × 9) + 1/2(8 × 17) = 54 + 68 = 122 cm2

ar(quad ABCD) = 1/2(12 × 9) + 1/2(8 × 15) = 54 + 60 = 114 cm2 ARE you interested to become my friend