OpenStudy (anonymous):

In z=2xy over d^2, z varies jointly as x and y and inversely as the square of d.

4 years ago
OpenStudy (anonymous):

This is true. Z is directly proportional to x and y separately, hence it is jointly variable to x and y. Z is inversely proportional to the square of d.

4 years ago
OpenStudy (anonymous):

thanks

4 years ago