1 Attachment(s)

..a very simple problem ..but different answers by different methods..

Attachment 20715

(see attached fig).

There is a triangle abc and an incircle to the triangle with radius 4cm.

The area of the triangle is given to be 84 cm^2

The base bc is divided by the radius into 6cm , 6cm

ab = ac

We need to find the value of these sides (ab or ac)

..

Methods of solving :

1)By using the pythagoras theorm, the answer comes to be appproximately 15 ( sqrrt(232) which is ~15

2)while by using area (1/2bh) the answer comes to be exactly 15..

what tis the reason for this difference?