ABC and BDE are two equilateral triangles such that D is the mid-point of BC. If the area of triangle ABC is 136 cm2, then the area of triangle BDE is equal to:
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e 34 cm2
| Understanding | Application |
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As both triangles are equilateral the ratio of the respective sides is constant.
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⇒ BC / BD = AC / ED = AB / BE We know that ⇒ ar(∆ABC) / ar(∆BDE) = BC2 / BD2 ⇒ 136 / ar(∆BDE) = BC2 / (BC / 2)2 ⇒ ar(∆BDE) = 136/4 ⇒ 34cm2 |