Geometric Terms Tools A B obtuse angle An angle greater than 90 degrees. hexagon A six sided figure. closed curve A curve that is continuous with meeting end points. circle A closed plane. rectangle A quadritlateral with opposite sides parallel. point A position in space. line A continuous extent of length. line segment One part of a line. radius A straight line extending from the center of a circle to the surface. chord The line segment between two points on a given curve. perpendicular lines Two lines that cross each other to form a 90 degree angle. intersecting lines Lines that cross each other. square A rectangle having all four sides of equal length. pentagon A polygon with 5 sides and 5 angles. right triangle A triangle with one internal angle egual to 90 degrees. vertex The intersection point of two lines. scalene triangle A triangle having three unequal sides and angles. equilateral triangle A triangle with all sides equal. right angle A 90 degree angle.