5 Mid-Chapter Quiz

Do you know HOW?

Each rate of change is constant. Find the rate of change and explain what it means.

1. Studying for a Test

   Study Time (h)	Grade
   5	85
   6	87
   7	89
   8	91

2. Distance a Car Travels

   Time (s)	Distance (m)
   3	75
   6	150
   9	225
   12	300

Find the slope of the line that passes through each pair of points.

3. (7, 3), (5, 1)
4. ( − 2 , 1 ) , ( 3 , 6 ) open negative 2 comma 1 close comma open 3 comma 6 close
5. ( 6 , − 4 ) , ( 6 , 6 ) open 6 comma negative 4 close comma open 6 comma 6 close
6. ( 2 , 5 ) , ( − 8 , 5 ) open 2 comma 5 close comma open negative 8 comma 5 close

Tell whether each equation is a direct variation. If it is, find the constant of variation.

7. y = 3 x y equals 3 x
8. 5 x + 3 = 8 y + 3 5 x plus 3 equals 8 y plus 3
9. − 3 x − 35 y = 14 negative 3 x minus 35 y equals 14

Find the slope and y-intercept of the graph of each equation.

10. y = 1 5 x + 3 y equals , 1 fifth , x plus 3
11. 3 x + 4 y = 12 3 x plus 4 y equals 12
12. 6 y = − 8 x − 18 6 y equals negative 8 x minus 18
13. Credit Cards In 2000, people charged $1,243 billion on the four most-used types of credit cards. In 2005, people charged $1,838 billion on these same four types of credit cards. What was the rate of change?
14. Bicycling The distance a wheel moves forward varies directly with the number of rotations. Suppose the wheel moves 56 ft in 8 rotations. What distance does the wheel move in 20 rotations?

Write an equation in slope-intercept form of each line.

Graph each equation.

17. y = 4 x − 3 y equals 4 x minus 3
18. y + 3 = 1 2 ( x + 2 ) y plus 3 equals , 1 half , open x plus 2 close

Write an equation in point-slope form for the line through the given point and with the given slope m.

19. ( 2 , − 2 ) ; m = − 1 2 open 2 comma negative 2 close semicolon m equals negative , 1 half
20. ( 4 , 0 ) ; m = 4 open 4 comma 0 close semicolon m equals 4

Write an equation of the line that passes through each pair of points.

21. ( 4 , − 2 )  and  ( 8 , − 6 ) open 4 comma negative 2 close , and , open 8 comma negative 6 close
22. ( − 1 , − 5 )  and  ( 2 , 10 ) open negative 1 comma negative 5 close , and , open 2 comma 10 close

Do you UNDERSTAND?

23. Writing Describe two methods you can use to write an equation of a line given its graph.
24. Vocabulary How can you find the y-intercept of the graph of a linear equation?
25. Reasoning Can you graph a line if its slope is undefined? Explain.
26. Business A salesperson earns $18 per hour plus a $75 bonus for meeting her sales quota. Write and graph an equation that represents her total earnings, including her bonus. What does the independent variable represent? What does the dependent variable represent?

Table of Contents