Math vocab

Collinear points

Points on the same line

Coplanar points

points on the same point

Point

No shape, size but has location

plane

Length and width, but no thickness

Line

Continues forever in both directions has no thickness or width

Space

Set of all points

Length

The measure of a segment

Ray

Starts at an endpoint and continues forever in one direction

Angle bisector

A ray that cuts an angle in half

Segment bisector

A line ray or segment that intersects a segment at its midpoint

Line segment

Is a part of a line that has two end points

The intersection of two planes

Line

Polygon

Must be closed, must be formed by connecting line segments, each side intersects exactly two other sides but only at their endpoints

Sides

Line segments of a polygon

Vertex

Each endpoint where the sides meet

Vertices

Plural for vertex

Concave polygon

Has at least one angle that caves in

Convex polygon

No angles cave in

Triangle

Polygon with 3 sides

Quadrilateral

Polygon with 4 sides

Pentagon

Polygon with 5 sides

Hexagon

Polygon with 6 sides

Heptagon

Polygon with 7 sides

Octagon

Polygon with 8 sides

Nonagon

Polygon with 9 sides

Decagon

Polygon with 10 sides

Undecagon

Polygon with 11 sides

Dodecagon

Polygon with 12 sides

n-gon

Polygon with 13 or more sides, ex: 25-gon, 16-gon

Naming polygons

Name the polygon by starting at one vertex and go in order either counting clockwise or counter clockwise. Name with capital letters! Ex: BCDE BAEDC

Equilateral polygon

Polygon with all equal sides

Equiangular Polygon

Polygon with all equal angles

Regular polygon

All sides and angles are =

Perimeter

Distance around a figure

Circumference

Perimeter of a circle

Area

Space a figure takes up

Polyhedron

A solid with all flat surfaces ( NO CURVES ) that enclose a single region of space

Face

The sides of a polyhedron

Edge

The segment where the faces intersect

Vertex

The point where three or more edges intersect

Prism

A polyhedron with two parallel congruent faces called bases connected by rectangular faces

Naming prisms

Name it by the shape of the bases Ex:Pentagonal prism

Pyramid

A polyhedron that has a polygon for a base and triangular sides that meet at a point (vertex)

Cylinder

A solid with congruent parallel circular bases connected by a curved side

Cone

A solid with a circular base connected by a curved surface to a vertex

Sphere

Set of points that are the same distance from a given point. A sphere has no faces or bases.

Polyhedrons

Polyhedrons or prisms+pyramids are named by the shape of their bases