##### Chapter 11 Vocabulary

prism

a solid figure with two congruent polygons that are bases, connected with lateral faces that are rectangles.

congruent

having the same size and shape

polygon

a closed plane figure formed by 3 or more straight line segments that meet at points called vertices.

regular polygon

a polygon in which all sides are congruent and all angles are congruent is a regular polygon

unit cube

a cube that has a length, width and height of 1 unit

polyhedron

a solid figure with faces that are polygons

volume

the measure of the amount of space a solid figure occupies.

lateral face

a polygon that connects with the bases of a polyhedron

acute angle

an angle that measures less han 90 degrees

obtuse angle

an angle that measures more than 90 degrees and less than 180 degrees

reflex angle

an angle that is greater than 180 degrees

equilateral triangle

a triangle where all sides are equal

isosceles triangle

a triangle with only two equal sides and angles

scalene triangle

a triangle with no equal sides or angles

base

a plane figure that is usually a polygon, used to describe and help find the volume of a solid figure