The Circles ClipArt gallery offers 166 Illustrations of circles with radii, diameters, chords, arcs, tangents, secants, and inscribed angles. Images also include inscribed, circumscribed, and concentric circles.

Illustration of circle with inscribed angle and central angle.

Inscribed and Central Angles

Illustration of circle with inscribed angle and central angle.

Illustration of circle with inscribed angle 30 and central angle 60.

Inscribed and Central Angles 30 60

Illustration of circle with inscribed angle 30 and central angle 60.

Illustration showing arcs measured in positive and negative angles.

Positive and Negative Arcs in Circles

Illustration showing arcs measured in positive and negative angles.

"In the triangle above, the line AB is its altitude. Since we know how to find the area of one triangle, we can find the areas of as many triangles as we have made from our circle. Therefore, to find the area of a circle: Find the area of one of the triangles and multiply by the number of triangles." -Foster, 1921

Area of Circle with Triangles

"In the triangle above, the line AB is its altitude. Since we know how to find the area of one triangle,…

Illustration of circles used to find area between two circles (ring).

Area of Circles and Rings

Illustration of circles used to find area between two circles (ring).

Illustration of circle with diameter.

Circle with Diameter

Illustration of circle with diameter.

A circle with labels for radius, diameter, and circumference. The visual will help to remember what each term means.

Circle Parts

A circle with labels for radius, diameter, and circumference. The visual will help to remember what…

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

Circle to Circle Tangents

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

Illustration of circle with 10 inch diameter and square.

Circle With 10 inch Diameter and Steel Square

Illustration of circle with 10 inch diameter and square.

Design made by drawing one large circle and then three circles that are internally tangent to the original circle and externally tangent to each other. The lines of centers of the inner circles form an equilateral triangle. Erase one side of each of the smaller circles to create the design. It resembles the yin and yang symbol.

3 Yin Yang Design Symbols In A Circle

Design made by drawing one large circle and then three circles that are internally tangent to the original…

Design made by drawing one large circle and then three circles that are internally tangent to the original circle and externally tangent to each other. The lines of centers of the inner circles form an equilateral triangle.. Erase one side of each of the smaller circles to create the design. It resembles the yin and yang symbol.

3 Yin Yang Design Symbols In A Circle

Design made by drawing one large circle and then three circles that are internally tangent to the original…

Design made by drawing one large circle and then four circles that are internally tangent to the original circle. Erase one side of each of the smaller circles to create the design. It resembles the yin and yang symbol.

4 Yin Yang Design Symbols In A Circle

Design made by drawing one large circle and then four circles that are internally tangent to the original…

Design made by drawing one large circle and then four circles that are internally tangent to the original circle. Erase one side of each of the smaller circles to create the design. It resembles the yin and yang symbol.

4 Yin Yang Design Symbols In A Circle

Design made by drawing one large circle and then four circles that are internally tangent to the original…

Illustration of circle with 6 inch diameter.

Circle With 6 inch Diameter

Illustration of circle with 6 inch diameter.

Illustration of circle with 8 inch diameter.

Circle With 8 inch Diameter

Illustration of circle with 8 inch diameter.

Illustration of a circle with the arc aeb drawn and labeled.

Arc of Circle

Illustration of a circle with the arc aeb drawn and labeled.

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

Arc of Circle

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.

Circle with Arc, Chord, Inscribed Angle, Circumscribed Polygon

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

Illustration of circle with arc and chord.

Arc and Chord in Circle

Illustration of circle with arc and chord.

A design created by inscribing 4 congruent tangent arcs in a circle.

Arcs Inscribed In A Circle

A design created by inscribing 4 congruent tangent arcs in a circle.

Illustration of circle with parts drawn to show area.

Area of a Circle by parts

Illustration of circle with parts drawn to show area.

Illustration of a circle with squares drawn to demonstrate area.

Area of Circle

Illustration of a circle with squares drawn to demonstrate area.

An illustration used to show how the area of a circle is calculated. Area is equal to the product of pi and the radius squared.

Area Of A Circle

An illustration used to show how the area of a circle is calculated. Area is equal to the product of…

Illustration of a circle with central angle AOB.

Central Angle in a Circle

Illustration of a circle with central angle AOB.

Illustration of a circle that can be used to show that an "angle at the center of a circle is measured by its intercepted arc."

Central Angles and Arcs in a Circle

Illustration of a circle that can be used to show that an "angle at the center of a circle is measured…

Illustration of a circle that can be used to show that an "angle at the center of a circle is measured by its intercepted arc." Angle AOB and angle COE are commensurable.

Central Angles and Arcs in a Circle

Illustration of a circle that can be used to show that an "angle at the center of a circle is measured…

Illustration of a circle that can be used to show that an "angle at the center of a circle is measured by its intercepted arc." Angle AOB and angle COE are incommensurable.

Central Angles and Arcs in a Circle

Illustration of a circle that can be used to show that an "angle at the center of a circle is measured…

Illustration of a circle showing an angle included by a tangent and a chord drawn from the point of contact. The angle is measured by half the intercepted arc.

Circle With Chord and Tangent

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

Illustrations of a circle with a chord and triangle inside.

Circle with Chord and Triangle

Illustrations of a circle with a chord and triangle inside.

Illustration of a circle with the chord eb drawn and labeled.

Chord of Circle

Illustration of a circle with the chord eb drawn and labeled.

Circle with intersecting chords.

Circle With Intersecting Chords

Circle with intersecting chords.

Circle with chords.

Circle With Chords

Circle with chords.

Illustration of a circle with diameter AB. Radii are RO, SO, AO, and BO. ED is a chord.

Chords, Diameters, and Radii of a Circle

Illustration of a circle with diameter AB. Radii are RO, SO, AO, and BO. ED is a chord.

Illustration of a circle with diameter BC, chord DF, secant MN, and tangent HK.

Chords, Secants, Diameters, and Tangents of a Circle

Illustration of a circle with diameter BC, chord DF, secant MN, and tangent HK.

Illustration of a circle which illustrates that through three points not in a straight line one circumference, and only one, can be drawn.

Circle With Circumference Through Three Points

Illustration of a circle which illustrates that through three points not in a straight line one circumference,…

A circle in its common, or central form. This is used to assist students in finding the equation of any circle.

Common Form of Circle

A circle in its common, or central form. This is used to assist students in finding the equation of…

Illustration of a circle with diameter and chord drawn. A diameter perpendicular to a chord bisects the chord and the arcs subtended by it.

Circle With Diameter and Chord

Illustration of a circle with diameter and chord drawn. A diameter perpendicular to a chord bisects…

Illustration showing a circle with a diameter, radius, and segment drawn.

Circle With Diameter, Radius, Segment

Illustration showing a circle with a diameter, radius, and segment drawn.

Illustration showing a circle with a diameter, radius, lines, triangle, and segment drawn.

Circle With Diameter, Radius, Segment, Line

Illustration showing a circle with a diameter, radius, lines, triangle, and segment drawn.

Illustration of a circle with two intersecting diameters.

Diameters of a Circle

Illustration of a circle with two intersecting diameters.

A circle divided evenly by a dotted line.

Divided Circle

A circle divided evenly by a dotted line.

Illustration of a circle with equal chords, which are equally distant from the center.

Circle With Equal Chords

Illustration of a circle with equal chords, which are equally distant from the center.

Illustration of a hexagon in a circle. Four of the six vertices of the hexagon are bound by the circle (are tangent to the circle). Because all six vertices are not on the circle, the hexagon is not cyclic; it is not inscribed in the circle.

Hexagon In A Circle

Illustration of a hexagon in a circle. Four of the six vertices of the hexagon are bound by the circle…

Illustration of a circle with an angle inscribed in a segment greater than a semicircle, an acute angle.

Circle With Inscribed Angle Greater Than Semicircle

Illustration of a circle with an angle inscribed in a segment greater than a semicircle, an acute angle.

Illustration of a circle with an inscribed angle.

Inscribed Angle in a Circle

Illustration of a circle with an inscribed angle.

Illustration of a circle with an angle inscribed in a segment less than a semicircle, an obtuse angle.

Circle With Inscribed Angle Less Than Semicircle

Illustration of a circle with an angle inscribed in a segment less than a semicircle, an obtuse angle.

Illustration showing the diameter of a circle inscribed in a right triangle is equal to the difference between the sum of the legs and the hypotenuse.

Circle Inscribed in a Right Triangle

Illustration showing the diameter of a circle inscribed in a right triangle is equal to the difference…

Illustration of a circle with a right angle inscribed in a semicircle.

Circle With Inscribed Right Angle in Semicircle

Illustration of a circle with a right angle inscribed in a semicircle.

Illustration showing a circle with equilateral triangles and another circle within.

Circle With Triangles and Circle Within

Illustration showing a circle with equilateral triangles and another circle within.

Circle with diameter, radius, arc, chord, and arc.

Circle With Parts

Circle with diameter, radius, arc, chord, and arc.

Illustration of circle with arc, chord, diameter  and radius.

Parts of Circle

Illustration of circle with arc, chord, diameter and radius.

Illustration of circle with perpendicular diameters.

Circle With Perpendicular Diameters

Illustration of circle with perpendicular diameters.

Illustration of circle with perpendicular diameters.

Circle With Perpendicular Diameters

Illustration of circle with perpendicular diameters.

"If from any point on the circumference of a circle, a perpendicular be let fall upon a given diameter, this perpendicular will be a mean proportional between the two parts into which it divides the diameter."

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,…

Illustration of circle with quadrant and 60 degree arc.

Quadrant of Circle With 60 degree Arc

Illustration of circle with quadrant and 60 degree arc.

Illustration of circle with radius of 4000, and triangle with 45 degree angle enclosed.

Circles With Radius 4000 and Enclosed Triangle

Illustration of circle with radius of 4000, and triangle with 45 degree angle enclosed.

Illustration of a circle with the radius OA drawn and labeled.

Radius of Circle

Illustration of a circle with the radius OA drawn and labeled.

Illustration of a circle with radius QR.

Radius of a Circle

Illustration of a circle with radius QR.

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

Radius, Diameter, and Chord In A Circle

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

Illustrations of a circle with secant AD and line BC tangent to it.

Circle with Secant and Point of Tangency

Illustrations of a circle with secant AD and line BC tangent to it.