The base of a triangular pyramid is a triangle with corners at (5 ,1 ), (2 ,7 ), and (3 ,4 ). If the pyramid has a height of 4 , what is the pyramid's volume?

1 Answer
Jan 19, 2017

2 unit^3

Explanation:

Volume of pyramid #=1/3 x base area x height

Let x_1=5, x_2=2,x_3=3, y_1=1,y_2=7 and y_3=4

Base area =1/2[[(x_1*y_2)+(x_2*y_3)+(x_3*y_1)]-[(y_1*x_2)+(y_2*x_3)+(y_3*x_1)]]

=1/2[[(5*7)+(2*4)+(3*1)]-[(1*2)+(7*3)+(4*5)]]
=1/2 [(35+8+3)-(2+21+20)]
=1/2 (46-43)
=3/2 unit^2

The volume =1/3*3/2*4 = 2 unit^3