Question

10. The sides of a triangle are 13 cm, 14 cm, and 15 cm. Then the area of the triangle is-
किसी त्रिभुज की भुजाएँ 13 सेमी, 14 सेमी और 15 सेमी है। उस त्रिभुज का क्षेत्रफल है
(a) 21 cm
(b) 48cm
(d) 74cm
(c) 84cm​

Answer 1

Answer:

c ) 84 cm

hope it help you

Answer 2

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Given

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• Sides of triangle = 13cm, 14cm and 15cm

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To Find

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• Area of Triangle

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Solution

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a = 13cm, b = 14cm and c = 15cm

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$\bf Semi \: perimeter = \frac{a + b + c}{2}$

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$\bf = \frac{13 + 14 + 15}{2}$

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$\bf = \frac{42}{2}$

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$\bf = 21$

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By using Heron's Formula

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

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$\bf = \sqrt{21(21 - 13)(21 - 14)(21 - 15)}$

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$= \bf \sqrt{21 \times 8 \times 7 \times 6}$

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$= \bf \sqrt{7056}$

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$\bf = {84cm}^{2}$

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Therefore, Area of triangle is 84cm square.