Heron's Formula


Name Computer Number


Construct an Acute Triangle ABC.

AB = BC = AC =

AB + BC + AC = (Let "s" equal the sum of the sides divided by 2.)

s= (s - AB) = (s - BC ) = (s - AC) =

Multiply s(s - AB)(s - BC)(s - AC) =

Take the square root of this value =

How does this final value compare with the area of the triangle from the computer?


Construct an Obtuse Triangle ABC.

Choose each vertex; construct polygon interior; measure Area =

AB = BC = AC =

AB + BC + AC = (Let "s" equal the sum of the sides divided by 2.)

s= (s - AB) = (s - BC ) = (s - AC) =

Multiply s(s - AB)(s - BC)(s - AC) =

Take the square root of this value =

How does this final value compare with the area of the triangle from the computer?


If you know the lengths of the sides of a triangle, you can use Heron's formula to find the area.

Let AB = a, BC = b, and AC = c.

What is Heron's Formula?


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