Question

Which of the following best describes the term direct variation?

A.Two variables exhibit direct variation if they have a constant ratio.
B. Two variables exhibit direct variation if they do not have a constant ratio.
C. Two variables exhibit direct variation if, when one variable increases, the other variable decreases.
D. Two variables exhibit direct variation if their products are always equal.

Answer 1

A. Two variables exhibit direct variation if they have a constant ratio

Answer 2

The best answer among the choices listed is option A. The statement that best describes the term direct variation is that "Two variables exhibit direct variation if they have a constant ratio". For instance, y is directly related to x. We can write in an equation by:

y = kx where k is the constant of proportionality and should be equal for all values of y and x.