Direct Variation and Functions

In a direct variation, y=39 when x=3.  Find the value of y when x=2.

• 26
• 3
• 58.5
• 2

 y varies directly with x, and y is 16 when x is 32. Which equation represents this situation?

• y=32x
• y=16x
• y=2x
• y=(1/2)x

Trina's paycheck earnings varies directly as the number of hours she works. If she works 19 hours and earns $187.15, what should she earn if she worked 40 hours? 

• $394
• $440
• $472.80
• $512.20

Is this a direct variation?

• yes
• no

Is this a direct variation?

• yes
• no

Which graph shows a proportional relationship between x and y?

• A
• B
• C
• D

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

• (0, 0)
• (1, 0)
• (0, 1)
• (1, 1)

Which graph shows a proportional relationship between x and y?

• A
• B
• C
• D

What is another name for k?

• y- intercept
• x 
• slope
• x- intercept

 Y varies directly with x, and y is 84 when x is 16. Which equation represents this situation?

• y=1344x
• y=100x
• y=5.25x
• y=4/21x