Answer:
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If y varies inversely as x then it has an equation:
- y = k/x, where k is coefficient
Substitute 4 for x and 16 for y to find the coefficient, k:
The equation is now y = 64/x.
Find the value of x when y = 9:
- 9 = 64/x
- x = 64/9 or 7 1/9