For these animations, click anywhere in the frame to advance to the next step.

When complete, look for the small buttons at the bottom of the page for supplementary viewing options.

- Prop. 11.11 To drop a perpendicular from a point to a plane
- Prop. 11.12 To draw a line perpendicular to a plane from a point on it
- Prop. 13.13 To construct an equilateral tetrahedron
- Prop. 13.14 To construct an equilateral octahedron
- Prop. 13.15 To construct a cube
- Prop. 13.16 To construct an icosahedron
- Prop. 13.17 To construct a dodecahedron