Question

A plot of land consisting of semicircle, a rectangle and a triangle. The length of the rectangle is three times the radius of the semicircle, the height of the triangle is twice the radius of the semicircle, and area of the rectangle is 120 sq. meter. Find the area pf the land.

Answer 1

Answer:

In △ABC AB=AC

⇒∠B=∠C (Angles opposite to equal sides are equal)

Now using angle sum property

∠A+∠B+∠C=180

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⇒80

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+∠C+∠C=180

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⇒2∠C=180

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−80

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⇒∠C=

2

100

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=50

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now ∠C+∠x=180

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(Angles made on straight line (AC) are supplementary)

⇒50

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+∠x=180

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⇒∠x=180

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−50

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=130

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