A triangle has sides with lengths: 16, 8, and 19. How do you find the area of the triangle using Heron's formula?

1 Answer
Dec 26, 2015

(see below for method)
Approximate area #63.2#

Explanation:

Heron's Formula tells us that if we are given a triangle with sides #a, b, c# and a semi-perimeter #s=(a+b+c)/2#, the area of the triangle is:
#color(white)("XXX")"Area"_triangle = sqrt(s(s-a)(s-b)(s-c))#

For the given values #(a,b,c)=(16,8,19)#
#color(white)("XXX")s=43/2#

#color(white)("XXX")(s-a)=11/2#
#color(white)("XXX")(s-b)=27/2#
#color(white)("XXX")(s-c)=5/2#

Applying the formula (and using a calculator)
#color(white)("XXX")"Area"_triangle ~~63.2#