### Equal Dihedral Angles

Illustration of 3 equal dihedral angles. "Two dihedral angles have the same ratio as their plane angles."

### Center of Gravity

"But if one of the balls be heavier than the other, then the centre of gravity will, in proportion,…

### Circle With a Perpendicular Drawn to the Diameter

"If from any point on the circumference of a circle, a perpendicular be let fall upon a given diameter,…

### Concentric Circles With Angle of 1 °

"If AOB is an angle of 1 ° on the larger circle, it is also 1 ° on the smaller concentric circle,…

### Equal Circles With Intercepted Arcs

Illustration of equal circles to show that two central angles have the same ratio as their intercepted…

### 2 Similar Right Circular Cones

Illustration of 2 right circular cones that are similar.

### 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…

### Similar Figures

2 circles that are similar figures

### Similar Figures

2 squares that are similar figures

### Similar Figures

2 rectangles that are similar figures

### Similar Figures

2 pentagons that are similar figures

### Model Of Geometric Proportions In A Circle

An illustration showing a model of a circle with intersecting chords that illustrates the following…

### Model Of Geometric Proportions In A Triangle

An illustration showing a model of a triangle that illustrates the following relationship: a:c = d:(b…

### Model Of Geometric Proportions

An illustration showing a quadrilateral model that illustrates the following relationships: a:b = c:d,…

### Model Of Geometric Proportions

An illustration showing a model that illustrates the following relationships: a:b = c:d, ad = bc. Product…

### Model Of Geometric Proportions

An illustration showing a model that illustrates the following relationships: a:b = c:b, ab = c²,…

### Model Of Geometric Proportions

An illustration showing a model that illustrates the following relationship: A:B = a:b.

### Model Of Geometric Proportions

An illustration showing a model that illustrates the following relationships: a:x = x:a - x, x = √(a²…

### Model Of Geometric Relationships In 2 Circles

An illustration showing a model of 2 circles with tangent lines, diameters, and radii that illustrates…

### Model Of Geometric Relationships In 2 Circles

An illustration showing a model of 2 circles with tangent lines, diameters, and radii that illustrates…

### Model Of Geometric Relationships In A Circle

An illustration showing a model of a circle with an exterior angle formed between a tangent and a secant…

### Model Of Geometric Relationships In A Circle

An illustration showing a model of a circle with angles formed between tangents and secants that illustrates…

### Proportions of human figure

"The proportions of the human figure. As handed down to us by Vitruvius and described by Joseph Bonomi."…

Illustration of an extension ladder. If ladder is leaned against a building, it will form a right triangle…

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned…

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned…

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned…

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned…

### Ladder Leaning Against a Building

Illustration of a ladder leaning against the side of a building (wall) to form a right triangle .

### Ladder Leaning Against a Tree

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a…

### Ladder Leaning Against a Tree

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a…

### Ladder Leaning Against a Tree

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a…

### Ladder Leaning Against a Tree

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a…

### 2 Ladders Leaning Against a Tree

Illustration of 2 ladders leaning against opposite sides of a palm tree to form similar right triangles.…

### 3 Ladders Leaning Against a Wall

Illustration of 3 ladders leaning against the side of a building (wall) to form right triangles. The…

### Lever Balanced on fulcrum With Weights

An illustration of a lever with weights m and n with distances a and b from fulcrum. Illustration could…

### Parallel Lines Cut by Transversals

Illustration that shows if two parallel lines are cut by three or more transversals that pass through…

### Parallel Lines Cut by Transversals

Illustration that shows if two parallel lines are cut by three or more transversals that pass through…

### Straight Lines to Find Ratios

Illustration of two straight lines that can be used to find ratios.

### Relationship Between 2 Parallelopipeds With Equal Altitudes

Diagram used to prove the theorem: "The rectangular parallelopipeds which have two dimensions in common…

### Similar Pentagons

Illustration of 2 similar pentagons.

### Similar Pentagons

Illustration of 2 similar 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…

### 3 Parallel Planes

"If two straight lines are cut by three parallel planes, the corresponding segments are proportional."

### Similar Polygons (Pentagons) That Can Be Used To Show Proportionality

Illustration that shows similar polygons (pentagons) that can be used to show proportionality.

### Similar Polygons (Pentagons) That Can Be Used To Show Proportionality

Illustration that shows similar polygons (pentagons) that can be used to show proportionality.

### 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…

### Similar Decagonal Prisms

Illustration of 2 similar right decagonal prisms. Both have regular decagons for bases and rectangular…

### Similar Heptagonal/Septagonal Prisms

Illustration of 2 similar right heptagonal/septagonal prisms. Both have regular heptagons/septagons…

### Similar Hexagonal Prisms

Illustration of 2 similar right hexagonal prisms. The height of the prism and length of the side of…

### Similar Hexagonal Prisms

Illustration of 2 similar right hexagonal prisms. The height of the prism and length of the side of…

### Divide A Line Proportionately

An illustration showing the construction used to divide the line AB in the same proportion of parts…