Today Andrew and I moved into the last chapter of the text. The first section is about polyhedrons and the number of edges, vertices, and faces they have. We looked at an example of a tetrahedron, pentahedron, and hexahedron. We counted the number of edges, vertices and sides and we noticed a pattern. We determined that F+V=E+2 would work for all 3D figures. Next we discussed cross sections. If we were to slice the figure straight down, what would the cross section look like. This was difficult for both of us to visualize. We used the online account to help us actually see what we were working with. We will continue with this lesson tomorrow.