Intro to Geometry

Geometry

The study of lines, 2D shapes, and 3D shapes

Basics

Lines, planes, rays, points

Line

Continues forever in both directions

Line Segment

Part of a line with two connecting points

Plane

2D object with no thickness extending infinitely

Ray

Part of a line starting from one point and extending in one direction infinitely

Complementary Angle

Two angles adding up to 90 degrees

Supplementary Angle

Two angles adding up to 180 degrees (form a flat line)

Acute Angle

Angle less than 90 degrees

Obtuse Angle

Angle greater than 90 degrees

Right Angle

Angle measuring 90 degrees

Alternate Interior and Exterior Angles

Congruent angles formed by two parallel lines and a transversal

Same-Side Interior and Exterior Angles

Angles on the same side of the transversal adding up to 180 degrees

Corresponding Angles

Congruent angles on the same side of the transversal

Vertical Angles

Opposite angles formed by intersecting lines measuring 90 degrees