7a. Icosidodecahedron 20/3 12/5 from truncation of icosahedron 20/3

Data

The distance from the centre of the icosahedron to the centre of the triangle is EP×0.76. The distance from the centre of the icosadodecahedron to the centre of the triangle (red) is EA×1.51. These two distances are equal, thus EA = EP/2.

Construction

EP is divided in two equal parts.

Twenty triangles (red) are applied on the 20 icosahedron triangles. The twelve corners (yellow) of the icosahedron are cut off, resulting in twelve pentagons (green-blue)

Line 1. Icosahedron, net and solid.

Line 2. Icosidodecahedron, net and solid