A triangle has sides with lengths: 1, 5, and 8. How do you find the area of the triangle using Heron's formula?

1 Answer
Jan 2, 2016

23i
This is an unsatisfactory result as it demonstrates that this triangle cannot exist.

Explanation:

Heron's formula states that the area of a triangle whose sides have lengths a, b, and c is:

A=s(sa)(sb)(sc)
where s is the semiperimeter of the triangle; that is,

s=a+b+c2

In this case; a = 1, b = 5, c = 8

Therefore s=1+5+82
s=7

By Heron: A=6.2.1=2.2.3i=23i