BC=10 cm,use the formula: Area of triangle/semi-perimeter of triangle= r, where "r" is the in-radius.Use hero's formula to find the area of the triangle, considering the reqd. side to be "x". You would get a quartic equation later on and that's the hardest part of the solution I feel and then you will get 10 cm as the answer.

Easy Math Editor

`*italics*`

or`_italics_`

italics`**bold**`

or`__bold__`

boldNote: you must add a full line of space before and after lists for them to show up correctlyparagraph 1

paragraph 2

`[example link](https://brilliant.org)`

`> This is a quote`

Remember to wrap math in \( ... \) or \[ ... \] to ensure proper formatting.`2 \times 3`

`2^{34}`

`a_{i-1}`

`\frac{2}{3}`

`\sqrt{2}`

`\sum_{i=1}^3`

`\sin \theta`

`\boxed{123}`

## Comments

Sort by:

TopNewestsorry...i don't get it....why we are using the formula: Area of triangle/semi-perimeter of triangle= r??

Log in to reply

the answer is nearly 10 but accurate is 9.78

Log in to reply

No, the answer is exactly 10 cm.

Log in to reply

BC=10 cm,use the formula: Area of triangle/semi-perimeter of triangle= r, where "r" is the in-radius.Use hero's formula to find the area of the triangle, considering the reqd. side to be "x". You would get a quartic equation later on and that's the hardest part of the solution I feel and then you will get 10 cm as the answer.

Log in to reply

sorry...i don't get it....why we are using the formula: Area of triangle/semi-perimeter of triangle= r?? can you explain further?

Log in to reply