Illustration showing the golden angle. The golden angle is the smaller of two angles created by dividing…

Illustration used to show how to "find an arc of a circle having a known radius, which shall be equal…

Illustration showing arcs measured in positive and negative angles.

Illustration used to show how to find the center when given an arc and its radius.

An illustration of an arc of a circle. An arc is any part of the circumference of a circle.

Illustrations of a circle with arc, chord, inscribed angle, and circumscribed about a polygon.

Illustration of a circle showing an angle included by a tangent and a chord drawn from the point of…

An illustration showing a circle with radius r, diameter d, and chord c.

Illustration of a sector of a circle. A sector is the space between an arc and two radii drawn to the…

Illustration of a sector of a hollow circle. A sector is the space between an arc and two radii drawn…

Illustration of a circle with two intersecting chords within the circumference. The angle formed is…

Illustration showing that from any point in the circumference of a circle, a chord and a tangent are…

Illustration used to show that "In equal circles, or in the same circle, if two chords are unequal,…

Illustration used to show that "In equal circles, or in the same circle, if two chords are unequal,…

Illustration showing angles formed by two secants, two tangents, or a tangent and a secant, drawn to…

Illustration showing various circles and the angles formed by intersecting lines.

"Join AB and BC, bisect AB and BC by perpendiculars. Their intersection will be the center of the required…

Always draw a circle in one stroke, inclining the compass in the direction of the line and rolling the…

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

The Byzantine interlacement band consists of wavy arcs and curves that have an angular bend. This design…

The Romanesque interlacement band consists of wavy arcs and curves that have an angular bend. It is…

The Romanesque interlacement band consists of wavy arcs and curves that have an angular bend.

Illustration used to show how to find a straight line of the same length as a given arc of a circle.

"A screw cut on a solid, of such form that if any plane be taken through its longitudinal axis, the…

An illustration showing a circle sector with radius r, center/central angle v, and length of circle…

An illustration showing a circle sector with center/central angle v and polygon angle w.

A sphere with arcs and poles. "The distance of all points in the circumference of a circle of a sphere…

Diagram showing 2 superimposed symmetrical spherical triangles.