What does this mean?

[Red Cardinal]

y is inversely proportional to the square root of x.
y = 4 when x = 9
Work out an equation connecting y and x

 

[JeffM]

What is the definition of inversely proportional?

 

[Deleted member 4993]

y is inversely proportional to the square root of x.
y = 4 when x = 9
Work out an equation connecting y and x

This means that you are required to convert the given word statement into mathematical statement.

For example, if they had said that:

y is proportional to x and y = 4 when x = 9, we would say:

y = k * x (k is some unknown numerical constant)

Now to calculate 'k', you know that, y = 4 when x = 9

4 = k * 9 \(\displaystyle \ \ \ \to \ \ \) k = 4/9

so

y = k * x = (4/9) * x

 

[Dr.Peterson]

For help on this sort of problem and the concepts involved, see

Directly Proportional and Inversely Proportional

Directly proportional: as one amount increases another amount increases at the same rate.

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