is perfectly straight and extends forever in both directions
is a perfectly flat surface that extends forever in all directions
is the part of a line between two points
is part of a line that starts at one point and extends forever in one direction
is formed by two rays with a common end-point called the vertex.
an angle that measures 90 degrees
an angle that measures more than zero but less than 90 degrees
an angle that measures more than 90 degrees, but less than 180 degrees
two angles whose measures add to 90 degrees
two angles whose measures add up to 180 degrees
figures that have the same shape and same size
a pair of opposite congruent angles formed by intersecting lines
Triangle Sum Theorem
states that the measures of the angles in a triangle add up to 180 degrees
has 3 acute angles
has one right angle
has one obtuse angle
has three congruent sides and angles
has at least two congruent sides and angles
has NO congruent sides or angles
is a closed plane figure formed by three or more sides
a polygon with congruent sides and angles
a quadrilateral with exactly one pair of parallel sides
a quadrilateral that has 2 pairs of parallel sides
a parallelogram with four right angles
a parallelogram with all side congruent
a parallelogram with four right angles and four congruent sides
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