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Plenty of geometry terms to study

acute angle An angle with measure greater than 0 degrees and less than 90 degrees.
acute triangle A triangle that has three acute angles
adjacent angles Two angles that have the same vertex, share a common side, and do not overlap.
angle Two rays with a common endpoint form an angle. The rays and vertex are used to name an angle.
arc A portion of the circumference of a circle.
asymmetry No symmetry
center of a circle A point inside a circle that is an equal distance from all of the points on its circumference.
center of rotation A fixed point around which shapes move in a circular motion to a new position.
central angle An angle whose vertex is the center of a circle and whose sides intersect the circle.
chord A segment with endpoints that are on a circle.
circle The set of all points in a plane that are the same distance from a given point called the center.
complementary angles Two angles are this if the sum of their measures is 90 degrees.
congruent Line segments that have the same length, or angles that have the same measure, or figures that have the same size and shape.
corresponding angles Angles that have the same position on two different parallel lines cut by a transversal.
diameter The distance across a circle through its center.
equilateral triangle A triangle with all sides congruent.
image Every corresponding point on a figure after its transformation.
isosceles triangle A triangle that has at least two congruent sides.
line A never ending straight path.
line of reflection The line that is reflected over in a reflection.
line of symmetry Each half of a figure is a mirror image of the other half when this is drawn.
line segment Part of a line containing two endpoints and all the points between them.
line symmetry A figure has this if a line can separate the figure into two congruent parts.
obtuse angle An angle with a measure greater than 90 degrees but less than 180.
obtuse triangle A triangle with one obtuse angle.
parallel lines Two lines in the same plane that do not intersect.
parallelogram A quadrilateral with oppostie sides parallel and congruent.
perpendicular lines Lines that intersect to form a right angle.
plane A two-dimensional flat surface that extends in all directions and contain at least three noncollinear points.
point An exact location in space that is represented by a dot.
polygon A simple closed figure in a plane formend by three or more line segments.
radius The distance from the center to any point on the circle.
ray A part of a line that extends indefinitely in one direction.
rectangle A parallelogram with four right angles.
reflection A transformation where a fgure is flipped over a line. Also called a flip.
regualar polygon A polygon having all sides congruent and all angles congruent.
rhombus A parallelogram with four congruent sides.
right angle An angle that measures 90 degrees.
right triangle A triange with one right angle.
rotation A transformation where a figure is turned around a fixed point. Also called a turn.
rotational symmetry A figure has this if it can be turned less than 360 degrees about its and still look like the original.
scalene triangle A triangle with no congruent sides.
sector A pie-shaped part of a circle by the radius of a circle and an arc.
Side-Side-Side Rule If all three sides in one triangle are the same length as the corresponding sides in the other, then the triangles are congruent.
skew lines Two nonparallel lines in space that do not intersect.
square A paralelogram with all sides congruent and four right angles.
straight angle An angle with a measure equal to 180 degrees.
supplementary angles Two angles are this if the sum of their measures is 180 degrees.
transformation A movement of a geometric figure.
translation A transformation where a figure is slid from one position to another without being turned. Also called a slide.
transversal A line that intersects two parallel lines to form eight angles.
trapezoid A quadrilateral with exactly one pair of parallel sides.
vertex A point where two sides of the polygon intersect; where three or more planes intersect in a point; the common endpoint of the rays forming an angle.
vertical angles Two pairs of opposite angles formed by two intersecting lines. The angles formed are congruent.
Created by: YungDaVinci