| A | B |
|---|
| decagon | a polygon with 10 sides and 10 angles |
| hexagon | a six-sided polygon |
| octagon | an eight-sided polygon |
| pentagon | a polygon with 5 sides |
| perpendicular | intersecting lines that cross to form 90 degree angles |
| polygon | three or more line segments in a plane that form a closed figure |
| quadrilateral | a polygon with four sides and four angles |
| vertex | the point of intersection for two sides of a plane figure, three sides of a solid figure, or the endponts of two rays that form an angle |
| vertices | the plural for vertex, the point where two lines intersect to make an angle |
| triangle | a three-sided polygon with three angles totaling 180 degrees |
| acute angle | an angle that measures less than 90 degrees but more than 0 degrees |
| angle | the figure formed when two rays meet at a common endpoint called a vertex |
| line | a straight path in a plane, extending in both directions with no endpoints |
| line segment | a part of a line between two endpoints |
| obtuse angle | an angle whose measure is greater than 90 degrees but less than 180 degrees |
| parallel | lines in the same plane that do not intersect |
| point | a position in space |
| ray | a part of a line that begins at one endpoint and extends forever in only one direction |
| right angle | an angle made when two line segments (or rays) meet to form a square corner |
| straight angle | an angle that measures 180 degrees |
