Verified Answer :

iGreen

Triangular Prism:

\(\sf~V=\dfrac{1}{2}\times~l\times~w\times~h\)

\(\sf~V=\dfrac{1}{2}\times7\times3\times3\)

\(\sf~V=3.5\times3\times3\)

\(\sf~V=10.5\times3\)

\(\sf~V=31.5\)

Break the Trapezoidal Prism into a rectangular prism with side measurements of 12, 18, and 6 and into a triangular prism with measurements of 6, 16, and 12.

Rectangular Prism:

\(\sf~V=lwh\)

\(\sf~V=(12)(18)(6)\)

Multiply all 3 numbers together:

\(\sf~V=1296\)

Now find the volume of the triangular prism:

\(\sf~V=\dfrac{1}{2}lwh\)

\(\sf~V=\dfrac{1}{2}(6)(16)(12)\)

Multiply all 4 numbers:

\(\sf~V=576\)

Add the two volumes together:

\(\sf1296+576=1872\)

Now we have to get rid of the area inside.

It's two rectangles both with lengths of 12 and widths of 6.

\(\sf~A=lw\)

\(\sf~A=(12)(6)\)

\(\sf~A=72\)

Multiply by 2 then subtract from the total volume we got:

\(\sf~72\times2 = 144\)

Subtract it:

\(\sf1872-144=1728\)