Corresponding Angles

Topic

Angles

Definition

Corresponding angles are pairs of angles that are in similar positions at each intersection where a transversal crosses two lines.

Description

Corresponding angles are used to determine whether two lines are parallel, as they are equal when the lines are parallel. They are commonly used in geometric proofs and problem-solving involving parallel lines and transversals. In real-world applications, corresponding angles are important in construction and design, where parallelism is crucial for structural integrity and aesthetics. For students, understanding corresponding angles helps develop skills in logical reasoning and geometric proofs, enhancing their overall understanding of geometry.

For a complete collection of terms related to Angles click on this link: Angles Collection.

What Are Angles?

In this illustration two rays intersect at a point. Points A and B are on one ray and points B and C are on another ray. These two rays form an angle.

The angle is the corner sweep formed by the two rays. Rays BA and BC form Angle ABC. 

Point B is the vertex of the angle. The vertex is the corner formed by the angle.

Angles can also be formed by intersecting lines. In this case four angles are formed when lines intersect.

The same happens when two line segments intersect, as shown below.

Geometric shapes are sometimes defined by the number of angles they have.

Even circles can contain angles, as shown below.

How Are Angles Measured?

Angles are measured in degrees or in radians. In this illustration, Angle ABC is a 30° angle.

Angles are also measured in radians. Radian measures are useful for indicating the portion of a circle an angle sweeps.

Use a protractor to measure an angle.