Direct Variation and Inverse Variation

Which equation represents an inverse variation?

As the speed of a train increases, the amount of time it takes to arrive at its destination decreases. What type of variation exists between the speed of the train and amount of time?

• Direct Variation

• Inverse Variation

• Neither

• Not enough information

Which of the given graphs is a direct variation?

• A

• B

• C

• D

Is the given table a direct or inverse variation? What is the constant of variation?

• Direct, 12

• Inverse, 12

• Direct, 1/12

• Inverse, 1/12

Write an equation for this relationship.

• y=4x

• y=1/8x

• y=1/4x

• y=8x

Is this a direct variation?
y=2x

• yes

• no

What ordered pair does a direct variation always go through when graphed?

• (0, 0)

• (1, 0)

• (0, 1)

• (1, 1)

Determine the type of variation:

• Direct

• Inverse

• Neither

Which of the following represents inverse variation?

• y = kx

• y = k/x

• y = x/k

• y = mx + b

If y varies inversely as x and x=5 when y=20, then what is the constant of variation, k? 

• 121

• 4

• 100

• 6