Geometry Terms

Front

Congruent

Back

Having the same size and shape; capable of being placed over another figure and exactly matching.

Tags

CCSS.8.G.A.2

Front

Adjacent sides

Back

Any two sides of a figure that share a common vertex.

Tags

CCSS.HSG.CO.C.11

Front

Diagonal

Back

A line segment in a polygon that connects two vertices but is not a side.

Front

Bisect

Back

To divide into two equal parts. A midpoint is the point where a line segment is divided into two congruent segments.

Front

Line of symmetry

Back

Divides a figure into two congruent parts, each of which is the mirror image of the other. Lines of symmetry are not limited to horizontal and vertical lines.

Tags

CCSS.4.G.A.3

Front

Parallel lines

Back

Lines that lie in the same plane and never intersect. They are always the same distance apart and do not share any points, having the same slope.

Tags

CCSS.4.G.A.1

CCSS.HSG.CO.A.1

Front

Perpendicular lines

Back

Lines that intersect at right angles.

Front

Vertex/Vertices

Back

The points where two or more line segments or edges meet, like a corner.

Tags

CCSS.4.G.A.1

Front

Plane

Back

A flat two-dimensional surface that extends infinitely in all directions.

Tags

CCSS.HSG.CO.A.1

Front

Interior Angles

Back

Any of the four angles formed in the area between a pair of lines when a third line intersects them.

Tags

CCSS.8.G.A.5