Solve x2 = 12x – 15 by completing the square. Which is the solution set of the equation?

A...(-6-square root of 51,-6+ square root of 51)
B.....(-6- square root of 21,-6+ square root of 21)
C...(6- square root of 51, 6+ square root of 51)
D...(6- square root of 21, 6 + square root of 21)

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