Answers

2014-11-20T23:45:04+08:00
Since Circle is circumscribe of the rectangle, The  corners of the rectangle are lies on the circle . And if we connect from one corner to the opposite corner of the rectangle that would be a Diameter.So by Pythagorean Formula.

D² = 9² + 7²
D =√130
r = 5.7        (ans.)

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