The sides of a triangle are `50 c m , 78 c m and 112 c m ` The smallest altitude is
(a) `20 c m `
(b) `30 c m `
(c) `40 c m`
(d) `50 c m `

Explanation

Let the sides of the triangles be `a=50cm, b=78cm and c=112cm`

semiperimeter of the triangle, `s=(a+b+c)/2`

`s=(50+78+112)/2`

`s=120`

Now, area of triangle by using heron's formula = `(ssqrt((s-a)(s-b)(s-c)))`

`(120sqrt((120-50)(120-78)(120-112)))`

`1680 cm^2`

`therefore` area of triangle = `1/2xxbasexxheight`

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