# Geometry Terms 1

## Terms

undefined, object
copy deck
an exact location
point
a straight path that extends without end in opposite directions
line
a flat surface that extends without end in all directions
plane
made up of two endpoints and all the points between the endpoints
line segment
has one endpoint. From the endpoint, it extends without end in one direction only
ray
measures less than 90 degrees
acute angle
measures 90 degrees
right angle
measures more than 90 degrees and less than 180 degrees
obtuse angle
two rays with a common endpoint
vertex
a triangle with all angles measuring less than 90 degrees
acute triangle
a triangle containing one obtuse angle
obtuse triangle
a triangle containing one right angle
right triangle
a triangle with no congruent sides
scalene triangle
a triangle with at least two congruent sides
isosceles triangle
a triangle with three congruent sides
equalateral triangle
a four sided polygon, or a plane with four sides and four angles
a figure formed by two rays with a common endpoint called the vetex
angle
a quadrilateral with two pairs of parallel sides
parallelogram
a parallelogram with four right angles
rectangle
a parallelogram with all sides congruent
rhombus
an angle that measures 180 degrees
straight angle
a pair of opposite congruent angles formed by intersecting lines
vertical angle
two angles that are side by side and have a common vertex and ray
two angles whose sum is 90 degrees
complementary angles
two angles whose sum is 180 degrees
supplementary angles
two lines that are opposite each other and never intersect
parallel lines
two lines that intersect to form a 90 degree angle
perpendicular lines
two lines on different planes and never intersect nor are they parallel
skew lines
a rectangle with four congruent sides
square
a quadrilateral with exactly one pair of parallel sides
trapezoid
a closed figure formed by three or more line segments that intersect only at their endpoints
polygon

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