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Find the area of an isosceles triangle having the base x cm and one side y cm.

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Question

Find the area of an isosceles triangle having the base x cm and one side y cm.

 
Short/Brief Note
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Solution

Let us assume triangle ABC be the given isosceles triangle having sides AB = AC and base BC. The area of a triangle ABC, say A having given sides AB and AC equals to cm and given base BC equals to x cm is given by

`A=1/2 " (Base" xx "Height)"`

Where,

Base = BC = x cm; Height = `sqrt(y^2 -x^2/4`

`A=1/2 " (Base" xx "Height)"`

   `=1/2 xx x (sqrt(y^2 -x^2/4))`

  `=x/2 (sqrt(y^2 -x^2/4))`

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Chapter 17: Heron’s Formula - Exercise 17.3 [Page 24]

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R.D. Sharma Mathematics [English] Class 9
Chapter 17 Heron’s Formula
Exercise 17.3 | Q 3 | Page 24

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