4. a. This table shows two points that are on the same straight line. Complete the table to show three other points on the same line.

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1 Moving Straight Ahead Study Questions 0. Sharon owns a bakery that makes cakes. She must pay a monthly rent for the bakery, and has to pay for ingredients for each cake. In January she made 300 cakes and her expenses where $2,930. In February she made 400 cakes and her expenses were $3,730 a. How much do the ingredients for a single cake cost? b. What is her monthly rent? c. write the equation that represents her expenses. d. If she charges $10 per cake, how many cakes does she need to sell to break even? e. Do her expenses represent a proportion? Explain. 1. The pep club is going to sell bouquets of flowers during the homecoming game. They represent their sales, R, and costs, C, with the following equations. R = 5.50x C = x x is the number of bouquets. a. When is the pep club s sales equal to their costs? Explain how you got your answer. b. What is the y-intercept for the line of each equation? What does it mean in this context? c. What is the constant rate of change for each relationship? What does it mean in this context? d. Are either of these relationships proportional? Explain how you know. 2 Brent's Video Shack charges $1.50 to rent a video game for a night. Mr. Buck's Entertainments opens a new store in town, charging $1.00 per night for a game, and starts to take customers away from Brent's Video Shack. a. Graph each price scheme on the same set of axes. b. How could Brent change his charges, so that he includes a one-time membership fee and drops his rental fee below Mr. Buck's, to get his customers back without losing too much money? Graph your proposal, and explain to Brent how it will work. c. Do either Brent s or Mr. Buck s charges represent a proportional relationship? Explain. 3. Does it make a difference what two points you choose on a straight line to find the slope of the line? Explain your answer. 4. a. This table shows two points that are on the same straight line. Complete the table to show three other points on the same line. b. Find the slope and the y-intercept of this line that represents the data.

2 5. Sam made up a set of tables based on some equations. He gave the tables to Adrian and challenged her to find the equations for each table. Adrian added two columns to each table to help her find the equations. Adrian used the extra columns to find the differences in x values and y values for each table. Below is the start of her work. a. Adrian used the extra columns to find the differences in x values and y values. Complete these columns for each table. b. Describe any patterns you see in the columns of differences. c. Find the equation of any table that represents a linear relationship. d. Explain why Adrian added the columns to the tables Sam gave her. Do you think it helped her to find the equations? Explain your thinking. 6. The formula relating n (the number of cricket chirps per minute) to t (the temperature in degrees Fahrenheit) is. a. Using a symbolic method, find how many times a cricket would chirp in a minute at 90º F. b. It is evening, and a cricket is chirping 48 times per minute. Use a symbolic method to find the temperature. 7 Each set of (x, y) coordinates below is generated by a linear rule. For each set of coordinates, write an equation to describe the rule. a. ( 1, 7), (0, -3), (1, 1), (2, 5), (4, 13), (5, 17) b. ( 2, 19), ( 1, 14), (0, 9), (2, 1), (4, 11), (6, 21) c. ( 2, 1), (0, 3), (1, 5), (3, 9), (5, 13), (6, 15)

3 8. Use the graph below to answer the questions. y x 1 Line A Line B a. Make a table showing the coordinates of four points located on line A. What is the equation for line A? b. Make a table showing the coordinates of four points located on line B. What is the equation for line B? c. Is there a point with (x, y) coordinates that satisfy both the equation for line A and the equation for line B? Explain your reasoning.

4 9. Here is a graph of three lines. a. Complete the chart. line A B C constant rate of change y- interce pt x- interce pt b. Here are the equations of the three lines. Match each line with its equation.,, line A:, line B:, line C: 10. Without graphing the lines, where is the point of intersection of these lines? and 11 a.find r if 2r + 10 = 22. b. Find x if 4.5x = 45. c. Find z if 3z 19 = 173. d. Find w if 67.1 = w.

5 12. The school drama club is performing its summer play at the community theater. Props for the play cost $250, and the theater is charging the drama club $1.25 for each ticket sold. So, the total cost C, for the drama club to put on the play is C = 1.25N + 250, where N is the number of tickets sold. Customers pay $4 for each ticket, so the total amount collected from ticket sales is T = 4N. a. What is the cost if 213 tickets are sold? b. How much is the total ticket sales if 213 tickets are sold? c. What is the drama club's profit or loss if 213 tickets are sold? d. If the total ticket sales are $780, how many people attended the play? e. What is the cost of putting on the play for the number of people you found in part (d)? f. How many tickets does the drama club need to sell to break even? g. The drama club would like to earn a profit of $500 from the play. How many tickets need to be sold for the club to meet this goal? 13. Solve the following equations for the value of x: a. 3x + 5 = 4x 10 b. 4x + 10 = 6x 8 c. 3x + 10 = 5x d. 3x 11 = 8x 21 e. 3(x + 8) = Do parts a-d for each pair of points below. i. (0, 0) and ( 3, -3) ii. (5, 1) and ( 3, 3) b. Find the slope of the line through the points. c. Compute the y-intercept. d. Using your answers from parts (a) and (b), write an equation for the line through the points. 15. In (a) (f), write an equation for the line that satisfies the given conditions. a. The slope is 7 and the y-intercept is -2. b. The slope is 0 and the y-intercept is c. The line passes through the points (3, 1) and (6, 4). d. The line passes through the points ( 24, 11) and ( 8, 3). e. The line passes through the points ( 4.5, 2) and (6.3, 5.8). f. The slope is and the line passes through the point (5, 0). 16. a. These two points determine a line: (0, 3) and (2, 5). Which of these points is also on that line? (4, 7) (4, 8) (4, 10) b. These two points determine a line: ( 2, 10) and (1, 4). Which of these points is also on that line? (2, 0) (2, 2) (2, 10)

6 17 To encourage customers, a new movie theater is offering memberships. The membership costs $75 a year plus $2 per movie. For non-members, the cost of a movie is $5.75. a. Make a table that shows the number of movies, (N), and the cost for members (C 1 ) and non-members (C 2 ). b. On the same set of axes, graph the relationship of cost and number of movies for members and non-members. c. Write an equation that shows the number of movies, (N), and the cost for members (C 1 ) and non-members (C 2 ). d. What is the slope of each line of the equations in part (c)? e. What information does the slope of each line represent in this context? f. Explain how you could find slope from a table. A graph? An equation? g. What information does the y-intercept of each line represent in this context? h. How many movies do you need to see a year for it to be worth it to become a member?