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Question
Find the area of a triangle, whose sides are :
10 cm, 24 cm, and 26 cm
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Solution
Sides of ∆ are
a = 10 cm
b = 24 cm
c = 26 cm
S = `(a + b + c)/2 = (10 + 24 + 26)/2`
= `60/2 = 30`
area of Δ = `sqrt(S(S - a)(S - b)(S - c))`
= `sqrt(30(30 - 10)(30 - 24)(30 - 26))`
= `sqrt(30 xx 20 xx 6 xx 4)`
= `sqrt(10 xx 3 xx 10 xx 2 xx 2 xx 3 xx 2 xx 2)`
= `sqrt(10 xx 10 xx 3 xx 3 xx 2 xx 2 xx 2 xx 2)`
= `10 xx 3 xx 2 xx 2 = 120 "cm"^2`
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