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Prove that the equilateral triangles described on the two sides of a right angled triangleare together equal to the equilateral triangle on the hyplotenuse in terms of their area |
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Answer» Step-by-step explanation: ANSWER Given: △ABC in which ∠ABC=90 ∘ and AB=BC. △ABD and △ACE are equilateral triangles. To PROVE: ar(ΔABD)= 2 1
×ar(ΔCAE) Proof: Let AB=BC=x units. ∴ CA= x 2 +x 2
=x 2
units. Now, ΔABD and ΔCAE being equilateral, has each angle EQUAL to 60 ∘
∴ΔABD∼ΔCAE But, the RATIO of the areas of two SIMILAR triangles is equal to the ratio of the squares of their corresponding sides. ∴ ar(ΔCAE) ar(ΔABD)
= CA 2
AB 2
= (x 2
) 2
x 2
= 2x 2
x 2
= 2 1
Hence, ar(ΔABD)= 2 1
×ar(ΔCAE) |
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