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Question
In ΔABC, if a = 18, b = 24, c = 30 then find the values of A(ΔABC)
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Solution
Given: a = 18, b = 24 and c = 30
∴ 2s = a + b + c
= 18 + 24 + 30
= 72
∴ s = 36
`A(ΔABC) = sqrt(s(s - a)(s - b)(s - c)`
`= sqrt(36(36 - 18)(36 - 24)(36 - 30)`
`= sqrt(36 xx 18 xx 12 xx 6)`
`= sqrt(36 xx 18 xx 4 xx 18)`
= 6 x 18 x 2
= 216 sq units.
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