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सी.आई.एस.सी.ई.आयसीएसई ICSE Class 8

Find the Area of a Triangle, Whose Sides Are : 21 M, 28 M and 35 M

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प्रश्न

Find the area of a triangle, whose sides are :

21 m, 28 m, and 35 m

बेरीज
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उत्तर

Sides of ∆ are
a = 21 m
b = 28 m
c = 35 m

S = `(a + b + c)/2 = (21 + 28 + 35)/2`

= `84/2 = 42`

area of Δ = `sqrt(S(S - a)(S - b)(S - c))`

= `sqrt(42(42 - 21)(42 - 28)(42 - 35))`

= `sqrt(42 xx 21 xx 14 xx 7)`

= `sqrt(7 xx 3 xx 2 xx 3 xx 7 xx 2 xx 7 xx 7)`

= `sqrt(7 xx 7 xx 7 xx 7 xx 3 xx 3 xx 2 xx 2)`

= `7 xx 7 xx 3 xx 2 = 294  "m"^2`

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 22: Area of a Trapezium and a Polygon - Exercise 20 (A) [पृष्ठ २२३]

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सेलिना Concise Mathematics [English] Class 8 ICSE
पाठ 22 Area of a Trapezium and a Polygon
Exercise 20 (A) | Q 1.3 | पृष्ठ २२३

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