



 
Hi Brian, Is a compass allowed? If so draw a circle of radius 10.5 inches with center C, and mark a point P on the circumference. With the compass setting unchanged put the point at P and mark two small arcs to intersect the circle at Q and R. Since the line segments PC, CQ and QP are of equal length the triangle PCQ is equilateral and hence the measure of the angle PCQ is 60 degrees. In a similar fashion the measure of the angle RCP is 60 degrees and thus the measure of the angle RCQ is 120 degrees. Finally extend the line PC to meet the circle at S. Q, R and S are the three points you need. Penny  


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