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Question
A triangle has sides 35 cm, 54 cm and 61 cm long. Find its area. Also, find the smallest of its altitudes ?
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Solution
The sides of a triangle are a = 35 cm, b = 54 cm and c = 61 cm
Now, perimeter a + b + c = 25
`⇒S= 1/2(35+54+61)`
⇒s= 75cm
By using heron’s formula
∴Area of triangle =`sqrt(s(s-a)(s-a)(s-c))`
`=sqrt(75(75-35)(75-54)(75-61))`
`sqrt(75(40)(21)(14))=93914cm^2`
∴ The altitude will be a smallest when the side corresponding to it is longest Here, longest side is 61 cm
∴ area altitude will be a smallest when the side corresponding to is longest here' longest side is 61 cm
∴area of Δ le = `1/2xxbxxh= 1/2xx base xx height `
`∴1/2xxhxx61= 939.14`
`⇒= (939.14xx2)/61= 30.79 cm`
๐ป๐๐๐๐ ๐กโ๐ ๐๐๐๐๐กโ ๐๐ ๐กโ๐ ๐ ๐๐๐๐๐๐ ๐ก ๐๐๐ก๐๐ก๐ข๐๐ ๐๐ 30.79 ๐๐
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