geometry

 

Circle O and circle P, with radii 3 and 8, respectively, are both tangent to line l at H. Enter all possible lengths of OP separated by commas.     

 

Sketch it.  If O & P are on opposite sides of I, then OP is 8 + 3  =  11     

                 If O & P are on the same side of  I, then OP is 8 – 3  =    5     

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