What is the area of a rhombus (in cm2) whose side is 20 cm and one of the diagonals is 24 cm?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 384.
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Concept |
Understanding |
Application |
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In rhombus, the diagonal bisect each other at right angle.
Area of rhombus = 1/2 × (Product of diagonals) |
Given: BD = 24 cm and AB = 20 cm Then, OB = 24/2 = 12 cm
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In right angle ∆AOB: AO2 = AB2 – OB2 AO2 = 202 – 122 AO = √(400 - 144) AO = √256 = 16 AO = 16 Hence, AC = 2AO = 32 cm Area of rhombus = 1/2 × AC × BD = 1/2 × 32 × 24 = 384 cm2 |
