x²- 6x = 72
Try x = 4,
4³ - 6(4) = 40 (smaller than 72)
Try x = 5,
5³ - 6(5) = 95 (bigger than 72)
Therefore, the answer has to be between 4 and 5.
Try x = 4.5
(4.5)³ - 6(4.5) = 64 (smaller than 72)
Try x = 4.7
(4.7)³ - 6(4.7) = 75.62
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Answer: The value of x is 4.7
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