You start from your home at A and run for 100m in west direction to reach point B. After that, you run for 50m in east direction to reach point C. Then you run for 100m in a South direction and reach point D. Which of the following is true?
BC ⊥ CD
If you draw the path on a paper, you will find it similar to the figure below. We can see that BC ⊥ CD.