
complementary
2 angles added together to equal 90

supplementary
2 angles added to equal 180

adjacent
right next to each other

vertical angles
across and equal to each other

linear pairs
2 adjacent angles that form a straight line

polygons
 3 or more sides
 straight lines
 no openings

vertex
where sides of a polygon join together

equilateral
all sides equal

convex
all vertices go out

equiangular
all angles are equal

regular
all sides are equal and all angles are equal

convex
all vertices go out

concave
at least one vertex goes in

point
 represents location
 no dimension

segment
starting and ending point

line
contains segment but goes on

ray
specific starting point then goes on

collinear
points that lie on same line


Coplanar
together on same plane

opposite rays
lines that share same starting points but go opposite ways


segment addition postulate
the sum of the parts equals the whole

midpoint
middle point of a line segment

midpoint formula
m= x_{1}+x_{2}/2, y_{1}+y_{2}/2

distance formula
square root of (x_{2}x_{1})^{2}+ (y_{2}y_{1})^{2}

angles
lines, rays, or segments that intersect

vertex
point at which lines rays or segments cross to form the angle

angle addition postulate
sum of the parts equals the whole






