| A | B |
|---|
| isosceles triangle | two sides the same length, one side different |
| scalene triangle | all three sides different lengths |
| equilateral triangle | all three sides equal lengths |
| right angle | angle measuring 90 degrees |
| obtuse angle | angle measuring more than 90 but less than 180 degrees |
| acute angle | angle measuring less than 90 degrees |
| protractor | tool used to measure angles |
| geometry | the study of shapes and angles |
