line - a straight path of points that continues without end in both directions, line segment - part of a line between two endpoints, ray - part of a line that has one endpoint and continues on without end in one direction, point - an exact location in space, angle - the amount of turning between 2 rays measured in degrees, quadrilateral - a polygon with 4 sides and 4 angles, equilateral triangle - a triangle with 3 equal sides and angles, isosceles triangle - a triangle with 2 equal sides and angles, scalene triangle - a triangle with 3 different sides and angles, symmetry - a shape has symmetry when one half of the shape is a mirror image of the other half, parallel lines - lines that are always an equal distance apart and will never intersect, perpendicular lines - lines that intersect to form right angles, right angle - an angle that measures exactly 90 degrees, acute angle - an angle that is less than 90 degress, obtuse angle - an angle that is greater than 90 degrees and less than 180 degress, straight angle - an angle that measures exactly 180 degrees, degrees - the unit used to measure the size of an angle, protractor - the tool used to measure degrees in an angle, intersect - when lines meet or cross over one another ,

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