How do you find the area given #a=12, b=15, c=9#?

1 Answer
May 25, 2017

Area #=54# sq. units

Explanation:

Assuming #a, b and c# are the three sides of a triangle we can apply Heron's formula to find the area.

Area#=sqrt(p (p−a )(p− b)(p−c)) #
where p is half the perimeter, or #(a+b+c)/2# (often called the semi-perimeter)

In this example: #a=12, b=15,c=9#

#p=(12+15+9)/2 = 18#

Area #=sqrt(18(18-12)(18-15)(18-9))#

#=sqrt(18xx6xx3xx9)#

#=sqrt(2916)#

#=54# sq. units