This mathematics ClipArt gallery offers 35 illustrations of right, acute, obtuse, reflex, straight, vertical, and adjacent angles.

Illustration of an angle

Angle

Illustration of an angle

Illustration that can be used to show the definition of an angle - an opening between two lines that intersect or meet.

Angle

Illustration that can be used to show the definition of an angle - an opening between two lines that…

Angle of degree 180

Angle Degrees 180

Angle of degree 180

Illustration to show that if an angle is bisected, and if a line drawn through the vertex perpendicular to the bisector, this line forms equal angles with the sides of the given angle.

Bisected Angle

Illustration to show that if an angle is bisected, and if a line drawn through the vertex perpendicular…

Illustration to show that the bisectors of two supplementary adjacent angles are perpendicular to each other.

Bisected Angles

Illustration to show that the bisectors of two supplementary adjacent angles are perpendicular to each…

Illustration to show that the bisector of one of two vertical angles bisects the other.

Bisected Angle

Illustration to show that the bisector of one of two vertical angles bisects the other.

Illustration to show that the bisector of two pairs of vertical angles formed by two intersecting lines are perpendicular to each other.

Bisected Angles

Illustration to show that the bisector of two pairs of vertical angles formed by two intersecting lines…

Illustration to show that if through any point in the bisector of an angle a line is drawn parallel to either of the sides of the angle, the triangle thus formed is isosceles.

Angle Bisector Drawn Parallel to A Side

Illustration to show that if through any point in the bisector of an angle a line is drawn parallel…

A dihedral angle is the opening between two intersecting planes.

Dihedral Angle

A dihedral angle is the opening between two intersecting planes.

An illustration of a plane angle with vertex E and sides EF and ED.

Plane Angle

An illustration of a plane angle with vertex E and sides EF and ED.

An illustration showing a straight angle. When the sides of an angle extend in opposite directions, so as to be in the same straight line, the angle is called a straight angle.

Straight Angle

An illustration showing a straight angle. When the sides of an angle extend in opposite directions,…

Four types of angles: right, obtuse, acute, and straight.

Angles

Four types of angles: right, obtuse, acute, and straight.

Showing different types of angles: right, acute, and obtuse.

Angles

Showing different types of angles: right, acute, and obtuse.

Illustration showing that the sum of all the angles about a point equals 360°.

360° Sum of Angles

Illustration showing that the sum of all the angles about a point equals 360°.

Illustration showing two positive angles; angle 1 being the acute angle and angle 2 being the reflex angle.

Acute and Reflex Angles

Illustration showing two positive angles; angle 1 being the acute angle and angle 2 being the reflex…

An illustration showing acute, obtuse, straight, right, and reflex angles.

Acute, Obtuse, Straight, Right, And Reflex Angles

An illustration showing acute, obtuse, straight, right, and reflex angles.

An illustration of two angles that are adjacent. They have the same vertex and a common side between them. Angles BOD and AOD are adjacent

Adjacent Angles

An illustration of two angles that are adjacent. They have the same vertex and a common side between…

Angles 1 and 2 are adjacent angles. Two angles with a common vertex and a common side between them are adjacent angles.

Adjacent Angles

Angles 1 and 2 are adjacent angles. Two angles with a common vertex and a common side between them are…

Illustration showing that the difference between angle 1 and angle 2 is angle ABC.

Difference of Angles

Illustration showing that the difference between angle 1 and angle 2 is angle ABC.

An illustration showing an angle the is greater than a right angle and less than a straight angle. This is an obtuse angle (solid curved arrow). The angle that is greater than a straight angle and less than two straight angles is called a reflex angle (dashed curved arrow).

Obtuse And Reflex Angles

An illustration showing an angle the is greater than a right angle and less than a straight angle. This…

Illustration of angles with parallel corresponding sides.

Angles With Parallel Sides

Illustration of angles with parallel corresponding sides.

Illustration of angles with parallel sides going in the opposite direction.

Angles With Parallel Sides

Illustration of angles with parallel sides going in the opposite direction.

Illustration of angles with parallel sides. "GH is parallel to and lies in the same direction as DE, and HI is parallel to but lies in the opposite direction to EF; hence, angle GHI is the supplement of DEF."

Angles With Parallel Sides

Illustration of angles with parallel sides. "GH is parallel to and lies in the same direction as DE,…

Illustration showing four angles that can be used to define different relationships, such as adjacent, supplementary, etc..

Relationships Between 4 Angles

Illustration showing four angles that can be used to define different relationships, such as adjacent,…

Illustration showing four angles that can be used to define different relationships, such as adjacent, supplementary, etc..

Relationships Between 4 Angles

Illustration showing four angles that can be used to define different relationships, such as adjacent,…

Illustration showing six angles that can be used to define different relationships, such as adjacent, supplementary, etc..

Relationships Between 6 Angles

Illustration showing six angles that can be used to define different relationships, such as adjacent,…

An illustration of angles with the same vertex made up of 4 lines.

Angles With Same Vertex

An illustration of angles with the same vertex made up of 4 lines.

Illustration showing that the sum of angle 1 and angle 2 is angle ABC.

Sum of Angles

Illustration showing that the sum of angle 1 and angle 2 is angle ABC.

Illustration of the superposition of two angles to compare magnitudes of the same kind.

Superposition of Angles

Illustration of the superposition of two angles to compare magnitudes of the same kind.

Illustration showing angles 1 and 2 are supplementary and angles ACD and DCB are supplementary. Also, Angles ACD and DCB are right angles.

Supplementary and Right Angles

Illustration showing angles 1 and 2 are supplementary and angles ACD and DCB are supplementary. Also,…

Vertical angles are when two angles have the same vertex, and the sides of the one are prolongations of the sides of the other. In this illustration, a and b are vertical angles and c and d are vertical angles.

Vertical Angles

Vertical angles are when two angles have the same vertex, and the sides of the one are prolongations…

Illustration showing that angles 1 and 2 are vertical and angles 3 and 4 are vertical.

Vertical Angles

Illustration showing that angles 1 and 2 are vertical and angles 3 and 4 are vertical.

Illustration of two angles whose sides are parallel, each to each, to show they are either equal or supplementary.

Angles With Parallel Sides

Illustration of two angles whose sides are parallel, each to each, to show they are either equal or…

Illustration showing that the bisector of a given angle is the locus of points equidistant from the sides of the angle.

Angle Bisector

Illustration showing that the bisector of a given angle is the locus of points equidistant from the…

"In geometry, an angle connected with an ellipse and defined as ... angle BCL, reckoned from one determinate end, B, of the transverse axis, called the eccentric angle of the point H." -Whitney, 1911

Eccentric Angle

"In geometry, an angle connected with an ellipse and defined as ... angle BCL, reckoned from one determinate…