Section 8.1 and 8.2/Rational Functions

Which equation represents inverse variation between x and y?

• 4y=kx

• xy=4k

• y=4kx

• 4k=x/y

The ordered pair (3.5, 1.2) is from an inverse variation. What is the constant?

• 2.3

• 2.9

• 4.2

• 4.7

Suppose x and y vary inversely, and x = 4 when y =9. Which function models the inverse variation?

• y=36/x

• x=y/36

• y=x/36

• x/y=36

Suppose x and y vary inversely, and x = -3 when y = 1/3. What is the value of y when x = 9?

• -9

• -1

• -1/9

• 1/9

In which function does t vary jointly with q and r and inversely with s?

• t = kq/rs

• t = ks/qr

• t = s/kqr

• t = kqr/s