Geometry vocab

vocab that we prob need to know for geometry test :)

parallel lines

two lines that are coplaner and do not intersect

skew lines

Lines that do not intersect and are not coplaner

parallel postulate

if there is a line and a point not on the line, then there is exactly one line through the point parallel to the given line.

transversal

a line that intersects two or more coplaner lines at different points

corresponding angles

two angles that occupy the same positions

alternate interior angles

angles between to two lines on opposite sides of the transversal

alternate exterior angles

angles outside the two lines on opposite sides of the transveral

same side interior angles

angles between the two lines on same sides of the transversal

congruent complements throrem

if two different angles are both complementary to the same angle (or congruent angles), then the two angles are congruent

congruent supplements theorem

if two different angles are both supplementary to the same angle (or congruent angles), then the two angles are congruent.

corresponding angles postulate

if two parallel lines are cut by a transversal, then the pairs of the corresponding angles are congruent.

alternate interior angles theorem

if two parallel lines are cut by a transversal, then the pairs of alternate interior angles are congruent.

alternate exterior angles theorem

if two parallel lines are cut by a transversal, then the pairs of alternate exterior angles are congruent

same side interior angles theorem

if two parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary

perpendicular transversal theorem

if a transversal is perpendicular to one of two parallel lines, then it is perpendicular to the other.

Plane

has 2 dimension. a flat serface that goes on infnity in all directions (looks like a tabletop)

collinear

points on the same line

coplanar

points on the same plane

segment

has endpoints

ray

has an initial point and extends one direction

congruent

having the same size and shape

midpoint

the point that divides or bisects a segments into two congruent segments.

segment bisector

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

equilateral

all sides are the same length

isosceles

a shape has two sides that are the same length

scalene

all three are different lengths and all angles are different too

perpendicular

2 lines that intersect to form a 90 degree angle

angle

to rays that have the same initial point. the rays are the sides and the initial point is the vertex

adjacent angles

angles that share a common vertex and side but have no common interior points.

vertical angles

angles that are opposite from each other when two lines cross. They are always congruent in measure.

complementary angles

two angles that measure up to 90 degrees

supplementary angles

two angles whose measures add up to 180 degrees

linear pair

two angles that are next to each other to form a line. their angles always add up to 180 degrees

angle addition postulate

if a point is inside an angle, then the two smaller angles add up to the bigger angle.