Question

if q is inversly proportional to the square of r and q is 4/81 when r is 9, find q when r is 2.

Answer 1

Firstly take q=a/r^2 as a general form

Answer 2

Now substitute in q=4/81 and r=9 so you have the equation:

4/81 = a/9^2

Ie

4/81 = a/81 and solve for a. Then use this value of a for the last part

Answer 3

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