| A | B |
|---|
| degree | a unit of measure for angles |
| acute angle | an angle that measures less than 90 degrees |
| straight angle | an angle that measures 180 degrees |
| protractor | an instrument used to measure the size of an angle |
| right angle | an angle that measures 90 degrees |
| obtuse angle | an angle that measures more than 90 degrees but less than 180 degrees |
| a line segment | a part of a line that has two end points |
| isosceles triangle | a trianlge that has at least two sides the same length |
| right triangle | a triangle with one right angle |
| scalene triangle | a triangle that has no sides the same length |
| equilateral triangle | a trianlge that has all sides the same length |
| acute triangle | an triangle that has all angles less than 90 degrees |
| obtuse triangle | a triangle that has one angle greater than 90 degrees |
| polygon | a plane, closed figure formed by line segments |
