# 13.4 Quiz: Linear Transformations and Direct Variation

The linear function f(x) = x . Which of the following equations could represent the function g(x) if

g(x) = 2f(x)+5 ?

• g(x) = x + 5

• g(x) = 2x + 5

• g(x) = 5x + 2

• g(x) = 5x/2

The linear function f(x) = x . The linear function g(x) = -3f(x) . Which of the following statements are true about the graphs of f(x) and g(x) ?

I. The slope of g(x) is steeper than the slope of f(x).

II. The line g(x) has a positive slope.

III. Both f(x) and g(x) intersect the y-axis at (0, 0).

• I and II

• I and III

• II and III

• I only

The value of y is directly proportional to the value of x. If y = 32 when x = 140, what is the value of y when x = 17.5?

y=

(enter the number only)

Mathematical Equivalence

ON

Heather works at Rad Records Inc. Heather’s weekly pay varies directly to the number of hours she works at the record store. Last week she worked a total of 24 hours and earned a total of $174. How much can Heather expect to earn if she works 35 hours next week?

(do not put $ in with your answer)

Mathematical Equivalence

ON

Tags

CCSS.HSF-LE.A.1B

The cost of juice is directly proportional to the amount of juice purchased. If 5 quarts of juice costs $6.25, how many quarts of juice can be purchased with $8.75? Which of the following statements are TRUE?

• y represents the cost of juice

• x represents the cost of juice

• y represents the amount of juice purchased

• x represents the amount of juice purchased

The number of mechanical pencils the workers at Sharpening Minds Co. can assemble varies directly with the number of hours the employees spend assembling the pencils. The employees can put 2,835 pencils together in 7.5 hours. If these employees continue to work at the same rate, how many pencils can they expect to put together in 46 hours?

Mathematical Equivalence

ON

The value of y varies directly with x. If x = 12, then y = 44. What is the value of x when y = 104.5?

(enter number and decimal only)

Mathematical Equivalence

ON

The value of y is directly proportional to the value of x. When x = 12, the value of y is 44. What is the value of y when x = 186?

(enter number only)

Mathematical Equivalence

ON

Answer explanation

Replace x with -6 and type in your calculator.

Tags

CCSS.8.F.A.1

CCSS.HSF.IF.A.1

Which of the given graphs is a direct variation?

• A
• B
• C
• D

Answer explanation

To be direct variation, a graph must be a LINE and pass through (0,0).

Tags

CCSS.8.EE.B.5