Suppose that y varies inversely as the square of x, and that y = 7 when x = 13. What is y when x = 17? (Round off your answer to 22 decima

Question

Suppose that y varies inversely as the square of x, and that y = 7 when x = 13. What is y when x = 17? (Round off your answer to 22 decimal points

Answer 1

If y varies inversely with x then y = k/x

where k is the constant of proportion.

 

For y varies inversely with x² then

y = k/x²

 

Plug in the given values of y and x to find k

 

7 = k/13²

k = 7(169) = 1183

 

Your formula is:  y = 1183/x²

 

Knowing the value of k, plug in the new value of x

to find y

 

y = 1183/17²

y = 1183/289

y = 4.093