front 1 Point  back 1 An exact location in space, usually represented by a dot 
front 2 Angle  back 2 A figure formed by two rays that have a common endpoint 
front 3 Vertex  back 3 The point where two or more rays meet; the point of intersection of two sides of a polygon; the point of intersection of three or more edges of a solid figure; the top point of a cone; the plural of vertex is vertices 
front 4 Circle  back 4 A closed plane figure with all points on the figure the same distance from the center 
front 5 Radius  back 5 A line segment with one endpoint at the center of a circle and the other endpoint on the circle 
front 6 Obtuse Triangle  back 6 A triangle that has one obtuse angle 
front 7 Polygon  back 7 A closed plane figure formed by three or more line segments 
front 8 Square  back 8 A rectangle with 4 equal sides 
front 9 Pentagon  back 9 A polygon with five sides 
front 10 Line  back 10 A straight path in a plane that goes on forever in opposite directions 
front 11 Right Angle  back 11 An angle formed by perpendicular lines, line segments, or rays and with a measure of 90° 
front 12 Parallel Line  back 12 Lines in a plane that never intersect 
front 13 Circumference  back 13 The distance around a circle 
front 14 Triangle  back 14 A polygon with three sides 
front 15 Equilateral Triangle  back 15 A triangle with three congruent sides 
front 16 Parallelogram  back 16 A quadrilateral whose opposite sides are parallel and congruent 
front 17 Trapezoid  back 17 A quadrilateral with one pair of parallel sides 
front 18 Closed Figure  back 18 A figure that begins and ends at the same point 
front 19 Line Segment  back 19 A part of a line that includes two points, called endpoints, and all of the points 
front 20 Acute Angle  back 20 An angle that has a measure less than a right angle (less than 90°) 
front 21 Perpendicular Lines  back 21 Two lines that intersect to form four right angles 
front 22 Chord  back 22 A line segment with its endpoints on a circle 
front 23 Right Triangle  back 23 A triangle with one right angle 
front 24 Isosceles Triangle  back 24 A triangle with two congruent sides 
front 25 Quadrilateral  back 25 A polygon with four sides 
front 26 Hexagon  back 26 A polygon with six sides and six angles 
front 27 Ray  back 27 A part of a line, with one endpoint, that continues without end in one direction 
front 28 Obtuse Angle  back 28 An angle whose measure is greater than 90° and less than 180° 
front 29 Intersecting Lines  back 29 Lines that cross at exactly one point 
front 30 Diameter  back 30 A line segment that passes through the center of

front 31 Acute Triangle  back 31 A triangle in which all three angles are acute 
front 32 Scalene Triangle  back 32 A triangle with no congruent sides 
front 33 Rectangle  back 33 A parallelogram with four right angles 
front 34 Octagon  back 34 A polygon with eight sides 