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Plane

A flat surface that extends indefinately in all directions.

Point

A dot that represents a location on a plane.

Line

A collection of points that extend indefinately in both directions.

Line Segment

Part of a line consisting of two endpoints and all the points between them.

Ray

Part of a line that has one endpoint and extends indefinately in one direction.

Polygon

A closed figure whose sides are straight line segments.

Triangle

A polygon with 3 sides.

Quadrilateral

A polygon with 4 sides.

Pentagon

A polygon with 5 sides.

Hexagon

A polygon with 6 sides.

Heptagon

A polygon with 7 sides.

Octagon

A polygon with 8 sides.

Nonagon

A polygon with 9 sides.

Decagon

A polygon with 10 sides.

Parallelogram

A quadrilateral with opposite sides parallel.

Rectangle

A parallelogram with 4 right angles.

Square

A rectangle with 4 sides of equal length.

Rhombus

A parallelogram with 4 sides of equal length.

Trapezoid

A quadrilateral with exactly one pair of parallel sides.

Types of Quadrilaterals

Parallelograms, rectangle, rhombus, trapezoid, square

Similar Figures

Figures that have the same shape but not necessarily the same size.

Corresponding Sides

A pair of sides from similar figures that are in the same position.

Corresponding Angles

A pair of angles from similar figures that are in the same position.

Congruent

To have the same measure.

Perpendicular Lines

Two lines that intersect at a right angle

Pi

The number that is the ratio of circumference of a circle to its diameter. 3.14159

Circle

The set of all points in a plane that are the same distance from a given point called the center

Radius

A line segment that has the center as one endpoint and a point on the circle as the other endpoint.

Diameter

The distance across a circle through the center.

Circumference

The distance around a circle.

Right Triangle

A triangle that has one right angle.

Hypotenuse

The side of a right triangle that is opposite the right angle. The longest side of a right triangle.

Legs

The sides of a right triangle that form the right angle.

Pythagorean Theorm

a2 + b2 = c2

Volume

The measure of the amount of space that an object occupies or how much it will hold. It is measured in cubic units.

Surface Area

The sum of the area of all the faces of a solid figure. SA is measured in square units.

Face

The flat surface of a solid figure.

Polyhedra

A solid that is bounded by polygons.

Square Pyramid

A figure whose base is a square and whose other faces are triangles that share a common vertex.

Rectangular Prism

A prism whose base is a rectangle.

Cone

A solid that has a circular base, a vertex, and a lateral surface area.

Cylinder

A solid figure with congruent circular bases that lie in parallel planes.

Ordered Pair

(x, y) Where x and y are values representing a point on a coordinate plane.

Rotation

A transformation that turns a figure a given angle and direction around a point.

Reflection

A transformation that flips a figure about a line into its mirror image on the opposite side of the line.

Translation

A transformation that slides each point of a figure the same distance in a given direction.

Dialation

Enlarging or reducing a figure proportionally.

Scale Factor

The common ratio of one polygon to a similar polygon.