What is the equation of the variation “d varies directly as r and s”?

A. = B. = C. =





D. =

8. What mathematical equation described the table of values below?

A. = 5 B. =

5



C. = 10 D. =

10



9. What equation represents “s varies directly as t and inversely as the u”?

A. = B. =





C. = D. =





10. In the statement “y varies directly as x, and = 12 when = 3”. What is the constant of variation?

A. 3 B. 4 C. 12 D. 36

11. In the statement “y varies inversely as x, and = 12 when = 3”. What is the constant of variation?

A. 3 B. 4 C. 12 D. 36​