36 terms

# Geometry

#### Terms in this set (...)

point
an exact location in space
line
an endless collection of points along a straight path
line segment
part of a line that has two end points
ray
part of a line that has one endpoint and extends endlessly in the other direction
plane
an endless flat surface that is named by any three parts not in the same line
intersecting lines
lines that have exactly one point in common; lines that touch
parallel lines
lines in the same plane that never intersect; lines that never touch
perpendicular lines
two lines that intersect at right angles
acute angle
an angle that measure less than 90 degrees
right angle
an angle that measures 90 degrees
obtuse angle
an angle with a measure greater than 90 degrees but less than 180 degrees
straight angle
an angle that measures 180 degrees
polygon
a closed plane figure with 3 or more sides
a 4 sided polygon
pentagon
a 5 sided polygon
hexagon
a 6 sided polygon
heptagon
a 7 sided polygon
octagon
a 8 sided polygon
nonagon
a 9 sided polygon
decagon
a 10 sided polygon
acute triangle
a triangle with 3 acute angles
obtuse triangle
a triangle with one obtuse angle
equilateral triangle
a triangle with all sides equal
isosceles triangle
a triangle with two congruent sides
scalene triangle
a triangle that has no congruent sides
parallelogram
a quadrilateral with 2 sets of parallel sides
rhombus
a parallelogram with 4 equal sides
square
a parallelogram with 4 right angles and 4 equal sides
rectangle
a parallelogram with 4 right angles
trapezoid
a quadrilateral with only 1 set of parallel sides
vertex
where edges meet
edge
where faces meet on a space figure
face
a flat surface on a space figure
right triangle
a triangle with one right angle
congruent
same shape same size
similar
same shape different size