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