Start out by drawing out your answer on graph paper.
Point A is at (0,0), Point B is at (10,0), Point C is at (10,10) Point D is at (0,10).
Then you can draw each of the lines. The equations for each of the lines are: DL: y = -2x + 10, NB: y = -2x + 20, OC: y = 1/2x + 5, and AM: y = 1/2x.
After drawing out all of the lines, you can find that Point R is at (6,8) and point P is at (4,2).
Use the distance formula or pythag to find the length between the two points.
√22+62=√40=2√10
Answer: 2√10
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