The base of a triangular pyramid is a triangle with corners at #(3 ,4 )#, #(6 ,2 )#, and #(5 ,5 )#. If the pyramid has a height of #7 #, what is the pyramid's volume?

1 Answer
Sep 14, 2016

#7/3# cu unit

Explanation:

We know the volume of pyramid = #1/3# * area of the base * height cu unit.
Here, the area of the base of triangle = #1/2[x1(y2-y3)+x2(y3-y1)+x3(y1-y2)]# where the corners are (x1,y1) = (3,4), (x2,y2) = (6,2) and (x3,y3) = (5,5) respectively.
So the area of the triangle =#1/2[3(2-5)+6(5-4)+5(4-2)]#
=#1/2[3*(-3) + 6*1 + 5*2]# = #1/2 * 2# = 1 sq unit
Hence the volume of pyramid = #1/3 * 1 * 7# = #7/3# cu unit