Direct and Inverse Variation

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

• y=1344x

• y=100x

• $y=\frac{21}{4}x$

• $y=\frac{4}{21}x$

Is the given table a direct variation? If so, what is the constant of variation?

• Yes; 1/3
• Yes; 3
• Yes; 5
• No

Tags

CCSS.HSA.CED.A.2

CCSS.HSF.LE.A.2

CCSS.HSS.ID.C.7

What kind of equation is this?

xy=8

• Inverse Variation

• Direct Variation

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

Tags

CCSS.HSA.CED.A.2

CCSS.HSF.LE.A.2

CCSS.HSF.IF.B.4

Which of the following represents direct variation?

• y = kx

• $y=\frac{k}{x}$

• $y=\frac{x}{k}$

• y = mx + b

Which of the following represents inverse variation?

• y = kx

• $y=\frac{k}{x}$

• $y=\frac{x}{k}$

• y = mx + b

The Height of a wave in California varies directly with the seconds that pass by. At 4 seconds, the wave is 6 feet high. How many seconds will give you a wave that is 10 feet high?

• $\frac{2}{3}$

• 6

• $\frac{20}{3}$

• 7

Which of the following is NOT a direct variation?

• y = -2x
• y = 1/2x
• 2x + 3y = 2
• 3y = 4x

Tags

CCSS.8.EE.B.6

CCSS.8.F.A.2

CCSS.8.F.A.3

CCSS.8.F.B.4

The amount of money earned on a job is directly proportional 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.HSA.CED.A.1

CCSS.HSF.LE.A.2

CCSS.HSA.SSE.A.1

CCSS.HSA.REI.B.3

CCSS.HSF.BF.A.1

CCSS.HSF.LE.A.1

What type of variation does this scenario represent?

The length of time you charge your cell phone

and the battery power

• direct variation

• inverse variation