| Step 1 | Place the protractor so that the origin (small hole) is over the point Q. |
| Step 2 | Rotate the protractor so that the base line is exactly along the line JK. |
| Step 3 | Using the inner scale, read the angle over the line LM. It should read 34 degrees. This shows that the angle ∠LQK has a measure of 34°. |
| Step 4 | Now, rotate the protractor so that its base line is along the line LM |
| Step 5 | Using the outer scale, read the angle over the line JK. It should read 34 degrees, showing that the angle ∠JQM also has a measure of 34°. |
| Step 6 | Done. By measuring these two angles, you have verified that vertical angles are congruent. |