### Circle to Circle Tangents

Equal circles inside and tangent to the outside circle, also tangent to each other

### 2 Similar Right Circular Cones

Illustration of 2 right circular cones that are similar.

### Coordinate Axis With Perpendiculars Drawn To Form Similar Right Triangles From Positive and Negative Theta, Θ

Angle XOP=Θ and angle XOQ=- Θ. From a point in the terminal side of each a perpendicular line is drawn…

### Coordinate Axis With Perpendiculars Drawn To Form Similar Right Triangles

Angle XOP=Θ and angle XOQ=90+Θ. From a point in the terminal side of each a perpendicular line is…

### 2 Narrow Cylinders on Their Sides

Illustration of 2 narrow right circular cylinders with equal heights (thickness) and different diameters.…

### 2 Right Circular Cylinders

Illustration of 2 right circular cylinders in which one cylinder is twice the height of the other.

### 2 Right Circular Cylinders

Illustration of 2 right circular cylinders in which one cylinder is twice the height and twice the diameter…

### 2 Similar Cylinders

Illustration of 2 similar cylinders. The height and diameter of the smaller cylinder is half that of…

### 2 Soup Can Cylinders

Illustration of 2 soup cans that are similar cylinders. The diameter and height of the smaller can is…

### 3 Similar Cylinders

Illustration of 3 similar cylinders. The height and diameter in each successively smaller cylinder is…

### 3 Similar Cylinders

Illustration of 3 similar cylinders. The height and diameter in each successively smaller cylinder is…

### 2 Concentric Decagons

Illustration of 2 regular concentric decagons.

### 2 Concentric Decagons

Illustration of 2 regular concentric decagons.

### 3 Concentric Decagons

Illustration of 3 regular concentric decagons that are equally spaced.

### 4 Concentric Decagons

Illustration of 4 regular concentric evenly spaced decagons.

### Hexagon Used to Construct Equivalent Triangle

Illustration of a how to construct a triangle equivalent to a given hexagon/polygon.

### Parallelogram Used to Construct Equivalent Square

Illustration of a how to construct a square equivalent to a given parallelogram.

### Pentagon Constructed to be Similar to Given Pentagons

Illustration of a how to construct a pentagon similar to two given pentagons.

### Pyramid Cut By Plane

Diagram used to prove the theorem: "If a pyramid is cut by a plane parallel to the base, the edges are…

### Similar Polyhedrons

Two similar polyhedrons may be decomposed into the same number of tetrahedrons similar, each to each,…

### Two Similar Polyhedrons

Diagram used to prove the theorem: "Two similar polyhedrons may be decomposed into the same number of…

### 2 Octagonal Prisms

Illustration of 2 right octagonal prisms with congruent bases, but different heights. The height of…

### 2 Rectangular Prisms

Illustration of 2 right rectangular prisms. The bases are congruent, but the height of the smaller prism…

### 2 Rectangular Prisms

Illustration of 2 right rectangular prisms. The bases are congruent, but the height of the smaller prism…

### 2 Similar Octagonal Prisms

Illustration of 2 Similar right octagonal prisms. The height and length of the edges of the smaller…

### 4 Congruent Rectangular Prisms

Illustration of 4 congruent rectangular prisms placed in the shape of a square. They are arranged to…

### 4 Hexagonal Prisms

A cluster of 4 right hexagonal prisms with congruent bases, but varying heights.

### 2 Right Pentagonal Pyramids

Illustration of 2 right pentagonal pyramids with hidden edges shown. The pentagonal bases are congruent,…

### 2 Right Rectangular Pyramids

Illustration of 2 right rectangular pyramids with hidden edges shown. The rectangular bases are congruent,…

### Similar Tetrahedrons

The volumes of two similar tetrahedrons are to each other as the cubes of their homologous (corresponding)…

### Two Proportional Tetrahedrons

Diagram used to prove the theorem: "Two tetrahedrons having a trihedral angle in each equal, are to…