Direct and joint variations

 y varies directly with x, and y is 84 when x is 16. What is the constant of proportionality?

• y = (21/4)x
• k= 21
• k= 5.25
• k= 4/21

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

• 26
• 3
• 58.5
• 2

Tags

CCSS.HSF-LE.A.1B

Is this a direct variation?
y=2x

• yes
• no

Tags

CCSS.8.EE.B.5

CCSS.8.EE.B.6

CCSS.8.F.A.3

CCSS.8.F.B.4

Which of the given graphs is a direct variation?

• A
• B
• C
• D

Tags

CCSS.8.EE.B.5

CCSS.8.EE.B.6

CCSS.8.F.B.4

The value of y varies directly with x.  Which function represents the relationship between x and y if y = 14 when x = 6. 

• y=20x
• y=84x
• y=7/3x
• y=3/7x

If y is directly proportional to x and  when, what is the value of y when?

• y=4
• y=6.25
• y=16
• y=18

Two quantities, x and y, are in a relationship in which y varies directly with x. The graph of the function contains the point (-16, 28). Which equation represents this situation?

• y=-448x
• y=-44x
• y=-4/7x
• y=-7/4x

Which graph shows a direct variation relationship between x and y?

• A

• B

• C

• D

Tags

CCSS.7.RP.A.2D

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

• 26
• 3
• 58.5
• 2

Tags

CCSS.8.EE.C.7

CCSS.8.F.A.1

CCSS.8.F.A.3

CCSS.8.F.B.4

The amount of money earned on a job varies directly to the number of hours worked. If $70.00 is earned in 5 hours, how much money is earned in 22 hours of work?

• $2

• $308

• $1.57

• $265

Tags

CCSS.8.EE.B.5

CCSS.8.F.B.4

CCSS.8.SP.A.3