



 
Priyam, I can give you some hints. Here is my diagram The sides of the trapezoid are tangent to the circle at $A, B, P \mbox{ and } Q.$ An important fact is that at each of these points the radius and tangent are perpendicular. $ACB$ is a straight line. Do you see why? Since the trapezoid is isosceles the symmetry of the diagram tells us that $B$ is the midpoint os the side $DE$ and hence you know the length of $BD.$ Triangles $PCD$ and $CBD$ are congruent. Do you see why? Thus you know the length of $PD.$ Can you complete the problem now? Write back if you need more help. Penny  


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