1. 11.1 Notes Space Figures and Cross Sections

2. Identifying Nets and Space Figures A polyhedron is a 3-dimensional figure whose surfaces are polygons. - each polygon is a face of the polyhedron - an edge is a segment formed by the intersection of two faces - A vertex is a point where three or more edges intersect What type of polyhedron is this?

3. Nets A net is a 2-dimensional pattern that you can fold to form a 3- dimensional figure. Net for a Cube: What faces will be opposite each other when you fold it?

4. Nets These nets will make the same polyhedron. Sketch the 3- dimensional figure created by these nets. What is the name of this polyhedron?

5. Euler’s Formula The number of faces (F), vertices (V), and edges (E) of a polyhedron are related by the formula: F + V = E + 2 Count faces and edges. Then use Euler’s Formula to find the number of vertices.

6. Euler’s Formula A polyhedron has 2 pentagons and 5 rectangles for a total of 7 faces. Use Euler’s Formula to find the number of vertices the polyhedron has. Draw a net for the above polyhedron. What is the name of this polyhedron?

7. Cross Section Cross section - the shape of a particular two dimensional “slice” of the polyhedron. The circle on the right is a cross-section of the cylinder on the left.

8. Cross -Section Draw a cross section formed by a vertical plane intersecting the front and right faces of the cube.

9. 11.1 HW Pg. 692-693 problems 1-29 odd, 38