Math, asked by ashraf9078, 1 year ago

Calculate the area of triangle whose sides are 18cm,24cm and 30cm in length.Hence, find the length of the altitude corresponding to the smallest side. Solution

Answers

Answered by tejasgupta
7

Heya !!

\text{Let's find out the area first.}\\\\\text{Area of a triangle by Heron's formula = $\sqrt{s(s-a)(s-b)(s-c)}$,}\\\\\text{where, a, b and c are the three sides of the triangle and s = $\dfrac{a+b+c}{2}= \dfrac{18+24+30}{2} = 36$}\\\\\text{Therefore, area of $\triangle = \sqrt{36(36-18)(36-24)(36-30)}$}\\\\= \sqrt{36 \times 18 \times 12 \times 6} = \large \underline{\boxed{\boxed{216 \: \: cm^2}}}

Now,

\text{Smallest side = 18 cm}\\\\\text{Let the height corresponding to it be $\alpha$.}\\\\\text{Area of $\triangle = \dfrac{1}{2} \times Base \times Height$}\\\\= \dfrac{1}{2} \times 18 \times \alpha = 9 \alpha\\\\\text{But, area of triangle was 216 $cm^2$.}\\\\\therefore 9 \alpha = 216\\\\\implies \alpha = \large \underline{\boxed{\boxed{24 \: \: cm}}}

Hope it helps !!

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