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point

a location on a plane or in space

Line

The set of all points on a plane in a single path that continues in opposite directions

Plane

The set of al points on a flat surface that extends in all directions

Line segment

Part of a line; Named by two endpoints.

Ray

The set of all points in a single path beginning at an endpoint and continuing in one direction

Angle

The joining of two rays to a common endpoint

Vertex

Endpoint of the angle

Acute

An angle that measures between 0 and 90 degrees

Right

An angle that measures 90 degrees

Obtuse

An angle that measures between 90 and 180 degrees

Straight

An angle that measures 180 degrees

Reflex

An angle that measures more than 180 degrees

Complementary

Two angles whose measures add up to 90 degrees are ____________.

Supplementary

Two angles whose measures add up to 180 degrees are _________.

Vertical

Angles that are nonadjacent that are formed when two lines intersect are __________ angles.

Parallel

Two lines on the same plane that will never intersect are __________ lines.

Corresponding

_________ angles are formed when a transversal cuts two or more other lines; They are on the same side of the transversal on the same side of the parallel line that forms each angle.

Alternate interior

Formed when a transversal cuts two or more lines; Opposite sides of the transversal, but on the einterior of the parallel lines.

Alternate Exterior

Opposite sides of the transversal on the exterior

Perpendicular

lines that meet to form right angles are _________.

Scalene

A triangle whose sides are each different lengths

Isosceles

A triangle in which two sides have the same measure

Equilateral

A triangle that has three congruent sides

Acute

a triangle with three acute angles

Obtuse

A triangle with one obtuse angle and two acute angles

Right

A triangle that contains one right angle and two acute angles. The two acute angles are complimentary.

Isosceles right

A triangle with two congruent sides, a right angle, and two acute angles that are equal in measure.

Scalene right

A triangle that contains sides each with different lengths, a right angle, and two acute angles that are complimentary, but not necessarily congruent.

Isosceles obtuse

A triangle that has two congruent sides, an obtuse angle, and two congruent acute angles.

Isosceles acute

A triangle that has two congruent sides and each of the angles is acute. The two acute base angles are congruent.

Similar figures

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

Similar

Triangles that have corresponding sides, or sides that line up, that are in proportion to each other are ________ triangles.