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A triangle with three acute angles
an angle that measures less than 90 degrees
two rays with a common endpoint, called the vertex
center of rotation
the fixed point a figure is rotated on during a rotation
points that lie on the same line
Two angles whose sum is 90 degrees
Angles that have the same measure
figures that have the same size and shape
Segments that have the same length
a unit for measuring angles
A triangle with 3 congruent sides
angles on the outside of parallel lines when cut by a transversal
result of a transformation of a point,line or plane
angles on the inside of the parallel lines when cut by a transversal
two lines that share exactly one point
A triangle with at least two congruent sides
a series of points that extends in opposite directions without end
line of reflection
The line over which a figure is reflected.
line of symmetry
A line that divides a figure into two halves that are mirror images of each other.
if you can draw a line throughit so that the 2 sides are mirror images of each other
An angle that measures more than 90 degrees but less than 180 degrees
a triangle with one obtuse angle
lines in the same plane that never intersect
A quadrilateral with both pairs of opposite sides parallel
Lines that intersect to form right angles
A flat surface that extends without end in all directions
a location in space that has no size
Three or more line segments in a plane that forms a closed figure. The line segments never cross but meet at their endpoints.
A polygon with four sides
a part of a line that begins at a point and continues without end in one direction
a parallelogram with four right angles
A transformation that "flips" a figure over a mirror or reflection line.
a parallelogram with four congruent sides
an angle that measures 90 degrees
a triangle with one right angle
A transformation that turns a figure about a fixed point at a given angle and a given direction.
a triangle with no congruent sides
part of a line with two end points
Figures that have the same shape but different sizes; their sides are proportional, while their corresponding angles are equal
lines that lie in different planes. they are neither parallel or intersecting
A parallelogram with four congruent sides and four right angles
an angle that measures 180 degrees
two angles whose measures have a sum of 180 degrees
A transformation that "slides" each point of a figure the same distance in the same direction.
A line that intersects two or more lines.
a quadrilateral with exactly one pair of parallel sides
the point of intersection of the two rays that form the sides of the angle
angles formed by two intersecting lines. Vertical angles are equal
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