G8 U6 Assessment

Name: ______________________________

Date:________________

Grade 8 Unit 6 Assessment Modeling Relationships with Functions 1. A rental car company charges a non-refundable deposit and a daily rate. Sasha rented a car for four days and was charged $190. Marlene rented a car for five days and was charged $225. Find the cost of the non-refundable deposit A. $45 B. $35 C. $47.50 D. $50 2. Find the rate of change in the graph of the function 12 10 8 6 4 2 0 0

2

4

6

8

10

.

A. −1.25 B. 10 C. −0.8 D. 8 Copyright © Swun Math Grade 8 Unit 6 Assessment, Page 1

3. Thirty-two degrees Fahrenheit is zero degrees Celsius, and 212℉ is 100℃. If the temperature dropped by 10℉, how much would the change be in degrees Celsius? A. −18℃ B. −18.9℃ C. −5.6℃ D. −4.7℃ 4. Find the rate of change in the function below x -5 0 3 7 10 f(x) 22 10 2.8 -6.8 -14 A. 10 B. 2.4 C. −1.4 D. −2.4

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5. Barney is about to buy several special calligraphy pens for $6.50 each. If he buys p pens, write a function for the amount of change, c, he will receive from a $50 bill. A. 𝐶 (𝑝) = 6.5𝑝 + 50. B. 𝑃(𝑐) = 50 − 6.5𝑐 C. 𝐶 (𝑝) = 6.5𝑝 − 50 D. 𝐶 (𝑝) = −6.5𝑝 + 50

6. Which graphs show a function that only increases in value when 𝑥 ≥ 0? Select all that apply. 8 6 4 I 2 0 -3 -2 -1 -2 0 1 2 3 -4 -6 -8

4

2

3

II

2 1

III

2

IV

1 -2

1 0 -2

-1

0 -1 0 -1

0 0

1

2

-2

A. I

B. II

C. III

D. IV

-1

0

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1

2

-2

1

2

7. Scott recently remembered an account that he used years ago and never closed. He starts depositing $100 per month, as the graph shows. How much was in the account when he started depositing? 600 500 400 300 200 100 0

-1

0

1

2

3

A. $250 B. $300 C. $200 D. $150 8. Jenny’s house was worth $198,000 in 2009 and $226,000 in 2013. At this rate how much will it be worth in 2020? A. $275,000 B. $254,000 C. $395,500 D. $226,800 Copyright © Swun Math Grade 8 Unit 6 Assessment, Page 4

9. Write a function that relates the values in the table below. x f(x)

-2 -5

4 10

10 25

A. 𝑓(𝑥 ) = 0.4𝑥 − 5 5

5

2

2

B. 𝑓(𝑥 ) = 𝑥 + C. 𝑓 (𝑥 ) = 2.5𝑥

D. 𝑓(𝑥 ) = 2𝑥 + 2 10. The water container below is filled by a small hose running at a constant rate. Which graph relates time on the horizontal axis and water level on the vertical axis? A

f(x)

B

f(x)

x

x

C

f(x)

D

f(x)

x

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x

11. Which linear function has a negative initial value but a positive rate of change? 5 4 3 2 1 0 -1 0 -2 -3 -4 -5

A B 1

C

2

D

A. Line A

B. Line B

C. Line C

D. Line D

12. The chart below shows the relationship between driving speed, s, and braking distance, d. s 20 30 40 50 60 d 14 31 58 90 130

Check if each statement about the relationship is correct. A. The initial value would be zero. Y N B. The function is linear.

Y

N

C. The function is increasing over the range shown.

Y

N

D. The rate of change is constant.

Y

N

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13. A large cheese pizza costs $9 plus $1.75 for each topping. Write a function equation relates the cost and the number of toppings. Answer: ________________________ 14. The graph below relates time and the height of a person above the center of the Ferris wheel he is riding.

Determine if the following statements are true. A. The graph shows two complete revolutions of the wheel.

T

F

B. The rate of change is constant.

T

F

C. The height is increasing twice on the graph.

T

F

T

F

D. The height is decreasing twice on the graph.

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15. Thirty-two degrees Fahrenheit is zero degrees Celsius, and 212℉ is 100℃. Write a function equation in which F depends on C.

Answer:__________________ 16. Sketch a graph of a function that is increasing when 𝑥 < 0, the 𝑓(0) = 4, and the function is decreasing when 𝑥 > 0.

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