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perpendicular line segments

Two line sements that intersect at right angles.

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line segment

A part of a line between and including two points, called endpointsof the segment.

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line

A 1-dimensional straight path that extends forever in opposite directions.

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ray

A part of a line starting at the endpoint and continuing forever in one direction.

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right angle

An angle that is 90 degrees.

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vertex

The point at which the rays of an angle meet.

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intersecting lines

Two lines that cross one another but do not for a 90 degree angle.

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convex

A polygon in which all vertices appear to be pushed outward.

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concave

A polygon in which at least one vertex appear to be pushed inward.

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quadrangle

A four-sided polygon

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parallel lines

Lines in a plane that are the same distance apart and never meet.

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rectangle

A parallelogram with all right angles.

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rhombus

A parallelogram with all sides the same length.

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trapezoid

A quadrilateral that has exactly one pair of parallel sides.

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parallelogram

A quadrilateral with two pairs of parallel.

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kite

A quadrilateral with two distinct pairs of adjacent sides of equal length.

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parallel rays

Two rays that are the same distance apart and never meet.

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radius

A line segment from the center of a circle to any point on the circle.

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diameter

A line segment that passes through the center of a circle and has endpoints on the circle

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circumference

The distance around a circle.

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chord

A line segment that has endpoints on the circle but does not pass through the center.

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