The Distance between Two Points
Read this article and watch the videos. Pay attention to the sections on the ruler postulate and the segment addition postulate. These two postulates help us perform certain measurements. The videos give examples. Read the examples near the end of the page closely to see step-by-step solutions.
Then, complete review questions 1, 2, 6, 7, 9, 10, 11, 16, and 17 and check your answers.