How do you use Heron's formula to determine the area of a triangle with sides of that are 35, 28, and 21 units in length?
1 Answer
Jan 16, 2016
Explanation:
First, determine the semiperimeter
#s=(a+b+c)/2#
We know that
#s=(35+28+21)/2=42#
Plug these into Heron's formula, which determines the area of a triangle:
#A=sqrt(s(s-a)(s-b)(s-c))#
#A=sqrt(42(42-35)(42-28)(42-21))#
#A=sqrt(42xx7xx14xx21)#
#A=sqrt(2^2xx3^2xx7^4)#
#A=2xx3xx7^2#
#A=294#
