HW30 – Unit 4 Test Review Name____________________________ Period________

Find the slope between the ordered pairs.

1. (-16,-15) and (-20,-7)

2. (0,-2) and (10,11)

3. (-13,-14) and (-13,0)

4. (13,9) and (19,9)

Fill in the blanks:

5. Slope-Intercept form is _____________________________

6. Standard form is _______________________________

7. Point-Slope form is _________________________________

8. The formula for slope is _________________________

9. The variable for slope is _________ and the variable for the y-intercept is _________

10. Slope is rise over ______________

Graph the line:

11. 12.

Write the slope-intercept form of the equation of the line through the given points.

21. (4,-2) and (5,-5) 22. (-3,2) and (-2,-1)

23. Joy is taking some college classes. She has to pay a flat fee of $8,000 and an additional $150 per unit. Which equation below represents how much Joy has to pay?

a.

b.

c.

d.

24. What is the slope of your equation in #23? What does it represent in the context of the situation?

25. What is the y-intercept of your equation in #23? What does it represent in the context of the situation?

26. Use your equation from #23 to find out how much Joy would have to pay if she only takes 8 units.

27. Joey and David’s teacher asked them to use the given point and slope to write an equation in slope-intercept

form. Their work is shown below. Explain who is right and who is wrong, and why.

Joey David

28. In 2012, Lexi bought a bracelet that was worth $21. In 2020, the same bracelet will be worth only $5.

a. What is the average annual rate of change of the worth of Lexi’s bracelet?

b. Write an equation in point-slope form to model the situation.

29. Jack is selling pails of water from atop his hill. If Jack sells 3 pails, he earns $5 profit. If Jack sells 11 pails, he

earns $29 profit.

a. Write an equation in slope-intercept form to model the situation.

b. Use your equation to estimate how many pails Jack would have to sell to earn a profit of $56.

c. What is the y-intercept of your equation? Why does it make sense that this value is negative?

30. Jill is a nurse for people when they fall down the hill. She charges a flat rate of $50 for her services, and an

additional $25 for every hour she works on someone’s head, stitching them up and bandaging them.

a. Write an equation in slope-intercept form to represent the situation.

b. Graph the situation. Be sure to label your axes appropriately.

Answer Key

1. -2

2.

3. Undefined 4. 0

5. 6. 7.

8. 9. m, b 10. run 11. Graph the point, then

use the slope! 12. Graph the point, then

use the slope!

21. 22. 23. d 24. The slope is 150,

which means that for each unit she takes, she has to pay $150.

25. The y-intercept is 8000, which means that if she takes 0 classes, she still has to pay a $8000 fee.

26. $9,200 27. Joey is incorrect because 6 divided by 3 is 2, not 3. David is incorrect because he added the 5 to both sides of the equation and got 8.

28. a. The bracelet is decreasing in value each year by $2.

28. b.

1 − (x 012)y − 2 = 2 − 2 29. a.

29. b. 20 pails of water 29. c. The y-intercept is -4 which makes sense because he has to pay for materials, so if he doesn’t sell any pails, he actually loses money ($4).

30. a. 30. b. Label the x-axis

“Hours”, label the y-axis

“Cost in $”. Graph it.

Re-read your notes, and STUDY!!!