Download pre ~ algebra vocabulary

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PRE ~ ALGEBRA VOCABULARY:
point – An exact location in space.
line – A straight path of points that extend without end in opposite directions.
plane – A flat surface that extends forever in all directions.
line segment – A part of a line consisting of two endpoints and all the points between them.
ray – A part of a line that starts at one endpoint and extends forever in only one direction.
intersecting lines – Two lines that have one point in common.
perpendicular lines – Lines that form 90 angles when they intersect.
parallel lines – Lines in the same plane that do not intersect.
angle – two rays that share a common endpoint. The rays are the sides of the angle and the point is the vertex of
the angle.
vertex – The point where the two rays meet in an angle.
right angle – An angle that measures 90. For an angle of x, {x : 0 < x < 90}
acute angle – An angle that measures greater than 0 and less than 90
obtuse angle – An angle whose measure is greater than 90 and less than 180.
straight angle – An angle that measures 180 or is formed by a straight line.
0 angle – a ray is a 0 angle.
complementary angles – Two angles whose measures have a sum of 90.
supplementary angles – Two angles whose measures have a sum of 180.
congruent angles – Angles that have the same measure.
vertical angles – A pair of opposite congruent angles formed by intersecting lines. Vertical angles are congruent.
adjacent angles – A pair of angle angles that share a common vertex and side.
parallel lines – Lines in the same plane that do not intersect.
transversal – a line that intersects two lines. A transversal forms 8 angles when it intersects two parallel lines.
corresponding angles – angles at the same location at each intersection when parallel lines are cut by a
transversal. Corresponding angles are congruent.
exterior angles – angles that are outside the parallel lines.
interior angles – angles that are inside (between) the parallel lines.
alternating exterior angles – angles that are on opposite sides of the transversal and are outside the parallel
lines. Alternating exterior angles are congruent.
alternating interior angles – angles that are on opposite sides of the transversal and are inside (between) the
parallel lines. Alternating interior angles are congruent.