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What is the area of a circle whose area is equal to that of a triangle with sides 7 cm, 24 cm and 25 cm?

A) \( \Large 80 cm^{2} \)
B) \( \Large 84 cm^{2} \)
C) \( \Large 88 cm^{2} \)
D) \( \Large 90 cm^{2} \)

Correct Answer:


B) \( \Large 84 cm^{2} \)

Description for Correct answer:

Given that, a = 7, b = 24 and c = 25

Semi-perimeter of triangle =\( \Large \frac{a+b+c}{2}=\frac{7+24+25}{2}=\frac{56}{2} \)=28 cm

According to the question,

Area of circle = Area of triangle

=\( \Large \sqrt{s(s-a)(s-b)(s-c)} \)

=\( \Large \sqrt{28(28 - 7)(28 - 24)(28 - 25)} \)

=\( \Large \sqrt{28\times 21\times 4\times 3}=\sqrt{7056} \)=\( \Large 84 cm^{2} \)

Part of solved Area and perimeter questions and answers : >> Elementary Mathematics >> Area and perimeter

Comments

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