Let $ABCDEFGH$ be a rectangular prism, where $EF = 4$, $EH = 5$, and $EA = 6$. Find the volume of pyramid $CFAH$.
Solution by 3D vecors! The pyramid is spanned by u = (4,5,0), v = (4,0,6), and w = (0,5,6). Taking the determinant gives us a volume of 42.