One word "Heron's formula" - Oh that's two words.Originally Posted byextreme_pi

Let be the semi-perimeter of a triangle with sides , and , that is:

.

Then area of the triangle is:

.

So in your case and so:

.

RonL

PS

You won't get banned for posting the samequestionmultiple times, but the

duplicates will be deleted. This is so that people do not waste their time

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