collinear points

points on the same line

congruent line segment

Line segments that have the same length


a location in space that has no size


a set of points that form a stright path extending in oppsite directions without end


figure formed by two rays with the same initial point


the pure mathematics of points and lines and curves and surfaces

noncolliear points

are points that do not lie on the same line

coplanar points

points all in one plane


the act of intersecting (as joining by causing your path to intersect your target's path), a place where two or more points meet

midpoint of a segment

The point that divides a segment into two congruent segments.


points on the ends of line segments


two dimensional flat surface, extends forever.


contains at least 4 points not in one line

obtuse angle

an angle between 90 and 180 degrees

straight angle

an angle of 180 degrees


formed by rays

opposite rays

two rays with the same initial point that go in opposite directions


the point of intersection of lines or the point opposite the base of a figure

bisector of a segment

a line, segment, ray, or plane that intersects the segment at its midpoint

acute angle

an angle less than 90 degrees but more than 0 degrees

congruent angles

Angles that have the same measure

right angle

the 90 degree angle between two perpendicular lines

vertical angles

angles are formed opposite of each other when two lines intersect

bisector of an angle

the ray that divides the angle into two congruent adjacent angles

perpendicular lines

two lines that meet and form a right angle



noncoplaner points

points that are not in the same plane


a part of a line with two endpoints

adjacent angles

Two angles with a common side, a common vertex, and no common points within the angles

supplementary angles

Two angles that add to 180º are called

complementary angles

if the sum of two angles is 90%


unit based to measure angles ( symbol )


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

perpendicular bisector

A line that is perpendicular to a segment at its midpoint.

corresponding angles

two angles in corresponding positions relative to two lines cut by a transversal

alternate exterior angles

Two nonadjacent exterior angles on opposite of the transversal.

same side-interior angles

interior angles on the same side of a transversal

exterior lines

The angle on the outside of a transversal.

skew lines

noncoplanar lines that do not intersect

parallel planes

planes that don't intersect

parallel lines

parallel lined


is a line that intersects each of two other coplanar lines in different points

interior angles

the angle inside of a transversal

alternate interior angles

two nonadjacent interior angles on opposite of the transversal

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