Geometry Vocab Unit 4

Front

Auxiliary line

Back

A line added to a figure to help you complete a proof or understand the figure.

Front

Interior Angle of a Triangle

Back

Angle formed by two sides of the triangle.

Front

Exterior Angle of a Triangle

Back

Angle formed by one side of the triangle and the extension of an adjacent side.

Front

Remote Interior Angle of a Triangle

Back

An interior angle that is not adjacent to a given exterior angle.

Front

Exterior Angle Theorem

Back

An exterior angle of a triangle is equal in measure to the sum of the two remote interior angles.

Front

Corollary

Back

An idea that follows from another. It is an extension of something we already know.

Front

Altitude

Back

A segment from a vertex of the triangle and perpendicular to the opposite side.

Front

Orthocenter

Back

Point of concurrency of the altitudes.

Front

Median

Back

A segment from a vertex of the triangle to the midpoint of the opposite side of the triangle.

Front

Centroid

Back

Point of concurrency of the medians.