# How do you use Heron's formula to determine the area of a triangle with sides of that are 28, 29, and 42 units in length?

##### 1 Answer

Apr 5, 2016

≈ 404.51 square units

#### Explanation:

This is a 2 step process.

step 1: Calculate half the perimeter (s) of the trianglelet a = 28 , b = 29 and c = 42

then s

#= (a+b+c)/2 = (28+29+42)/2 = 99/2 = 49.5 #

step 2: Calculate the area (A) using

# A = sqrt(s(s-a)(s-b)(s-c)) #

# = sqrt(49.5(49.5-28)(49.5-29(49.5-42))#

# = sqrt(49.5xx21.5xx20.5xx7.5) ≈ 404.51" square units " #