Practice A. Name Date. y-intercept: 1 y-intercept: 3 y-intercept: 25. Identify the x-intercept and the y-intercept of the graph.

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1 4. Practice A For use with pages Identif the -intercept and the -intercept of the graph Find the -intercept of the graph of the equation Copright b McDougal Littell, a division of Houghton Miffl in Compan Find the -intercept of the graph of the equation Draw the line that has the given intercepts.. -intercept:. -intercept: intercept: -intercept: -intercept: -intercept: 4. Algebra

2 4. Practice A continued For use with pages Match the equation with its graph A. B. C. Graph the equation. Label the points where the line crosses the aes Club Membership The computer club at our school is open to juniors and seniors. There are now 4 members in the club. Let be the number of junior members and let be the number of senior members. a. Write an equation for the total number of members in the club. b. Find the intercepts of the equation. c. Graph the equation.. Ticket Sales You sold tickets to the school pla. Advance tickets were $. Tickets sold at the door were $8. Total ticket sales were $48. This situation can be represented b the equation 8 48 where is the number of advance tickets sold and is the number of tickets sold at the door. a. Find the intercepts of the graph of the equation. b. Graph the equation. c. If advance tickets were sold, how man tickets were sold at the door? Senior members Tickets at the door Junior members 4 8 Advance tickets Copright b McDougal Littell, a division of Houghton Miffl in Compan. 4 Algebra

3 4. Practice B For use with pages Find the -intercept and the -intercept of the graph of the equation Draw the line that has the given intercepts.. -intercept:. -intercept:. -intercept: -intercept: 4 -intercept: -intercept: Graph the equation. Label the points where the line crosses the aes Copright b McDougal Littell, a division of Houghton Miffl in Compan Algebra

4 4. Practice B continued For use with pages Match the equation with its intercepts A. -intercept: 4 B. -intercept: 4 C. -intercept: 7 -intercept: 7 -intercept: 7 -intercept: 4. Rabbit Hutch The cage that ou keep our rabbit in has a perimeter of 8 inches. Let be the cage s width (in inches) and let be its length (in inches). a. Write an equation for the perimeter. b. Find the intercepts of the graph of the equation ou wrote. Then graph the equation. Length (inches) Width (inches) 4.. Home and Garden Show Admission to a home and garden show costs $7 per person during the week and $9 per person on the weekend. During one week of the show, a total of $4, was paid in admissions. This situation can be represented b the equation 7 9 4, where is the number of tickets sold during the week and is the number of tickets sold on the weekend. a. Find the intercepts of the graph of the equation. Graph the equation. b. Give three possibilities for the number of each kind of ticket that could have been sold for the week. 7. Burning Calories A man burns calories per minute mountain biking and 7. calories per minute in-line skating. His goal is to burn approimatel 4 calories dail. This situation can be represented b the equation 7. 4 where is the number of minutes spent mountain biking and is the number of minutes spent in-line skating. a. Find the intercepts of the graph of the equation. Graph the equation. b. What do the intercepts mean in this situation? c. What are three possible numbers of minutes of biking and skating the man could do to reach his goal? Algebra Weekend sales,,, 7,,, Minutes in-line sklating ,, Weekda sales Minutes mountain biking Copright b McDougal Littell, a division of Houghton Miffl in Compan.

5 4. Practice C For use with pages Find the -intercept and the -intercept of the graph of the equation } Draw the line that has the given intercepts.. -intercept:. -intercept: 7. -intercept: -intercept: -intercept: 4 -intercept: 9. -intercept: 4. -intercept: 8. -intercept: -intercept: -intercept: 8 -intercept: Copright b McDougal Littell, a division of Houghton Miffl in Compan. Graph the equation. Label the points where the line crosses the aes Algebra 7

6 4. Practice C continued For use with pages Summer Income You earn $ an hour mowing lawns and $ an hour washing windows. You want to make $ in one week. This situation can be represented b the equation where is the number of hours ou mow lawns and is the number of hours ou wash windows. a. Find the intercepts of the graph of the equation. Graph the equation. b. What do the intercepts mean in this situation? c. What are three possible numbers of hours ou could work at each job? d. If ou work hours washing windows, how man hours do ou have to mow lawns?. Fruit Baskets A small mail-order compan that sells fruit baskets currentl has 4 orders for fruit baskets. The person who assigns workers to tasks is tring to figure out how man workers need to be assigned to assembling fruit baskets in order to get them out on time. To do this, the person needs to know how man fruit baskets must be produced in one hour. The number B of fruit baskets left to assemble can be modeled b the function B 4 nh where n is the number of fruit baskets that can be assembled in one hour and h is the number of hours the compan has to produce the fruit baskets. B Hours washing 4 4 Hours mowing a. Graph the function if the baskets have to be assembled in 48 hours. Then identif the domain and range of this function. How man baskets per hour have to be assembled? b. Suppose baskets are made in the first 4 hours. How does this affect the graph? How man baskets per hour have to be assembled to finish the job? Total baskets Baskets per hour n Copright b McDougal Littell, a division of Houghton Miffl in Compan. 8 Algebra

7 4. Challenge Practice For use with pages In Eercises 7, write an equation of the line with the given - and -intercepts. Eample: -intercept: -intercept: 4 Solution: Multipl p 4. The equation is 4.. -intercept: 7, -intercept:. -intercept:, -intercept:. -intercept:, -intercept: 4. -intercept:, -intercept:. -intercept:, -intercept: b. -intercept: a, -intercept: intercept: a, -intercept: b 8. Does the process used in Eercises 7 alwas work? If not, what intercept values cause the process to fail? 4. In Eercises 9, use the following information. Mar is taking an eam consisting of multiple choice problems and essa problems. It takes Mar minute to complete a multiple choice problem and minutes to complete an essa problem. She has one hour to complete the eam. 9. Using to represent the number of multiple choice problems and to represent the number of essa problems, write an equation to show the relationship between how man multiple choice problems and how man essa problems Mar can complete in one hour.. What is the -intercept of the equation found in Eercise 9? What does this -intercept represent?. What is the -intercept of the equation found in Eercise 9? What does this -intercept represent? Copright b McDougal Littell, a division of Houghton Miffl in Compan. 44 Algebra

8 S Problem Solving Workshop: Mied Problem Solving For use with pages. Multi-Step Problem Plot the points (, ), (, ), (4, ), and (4, ) in a coordinate plane. Connect the points to form a rectangle. a. Find the length, width, perimeter, and area of the rectangle. b. The rectangle is a scale model of a rectangular garden. Each unit of the coordinate plane represents feet. Find the perimeter and area of the garden.. Multi-Step Problem The table below shows the number of miles ou run in the first four weeks of training for a -mile race.. Short Response A phone card charges $.8 per minute for a phone call. a. Find the cost of a minute call, a minute call, and a minute call. b. Plot the costs ou found in part (a) in a coordinate plane, where the -coordinate represents the length of the call (in minutes) and the -coordinate represents the total cost of the call (in dollars). c. What conclusions can ou make from the graph? d. Draw a line through the points. Use the line to estimate the cost of an hour-long call. Week 4 Miles a. At this pace, how far will ou run in week 7? b. At this pace, how man weeks do ou need to train to run miles?. Gridded Answer The graph shows the possible combinations of CDs and DVDs that ou can bu with the amount of mone ou have. If ou bu onl CDs, how man can ou bu? 4.. Short Response Your friend agrees to lend ou $ to bu a board game. You promise to pa our friend $.8 each week until ou have paid back the full $. Graph the function P.8n using intercepts, where P is the amount of mone in dollars that ou have left to pa and n is the number of weeks. Identif the domain and range of the function. Find the number of weeks it takes to pa back our friend. If ou decide to pa our friend $ each week, will it take ou more or less time to pa our friend back than if ou paid him $.8 each week? Eplain our reasoning. 4. Open-Ended Consider the equation 8 k. What is a possible value of k so that the -intercept and the -intercept are both integers? Eplain. Number of DVDs Number of CDs 7. Etended Response A bank offers a savings account at a % simple annual interest rate and a certificate of deposit at a 4% simple annual interest rate. You want to earn $ in interest the first ear. The equation.s.4c models the situation where s is the amount of mone placed in a savings account and c is the amount of mone placed in a certificate of deposit. Find the intercepts. Then graph the equation. What do the intercepts represent in terms of the situation? Describe how this information can be used to make a decision about how to invest our mone. Copright b McDougal Littell, a division of Houghton Miffl in Compan. 4 Algebra

9 4. Stud Guide For use with pages GOAL Graph a linear equation using intercepts. Vocabular The -coordinate of a point where a graph crosses the -ais is an -intercept. The -coordinate of a point where a graph crosses the -ais is a -intercept. EXAMPLE Find the intercepts of the graph of an equation Find the -intercept and the -intercept of the graph of 7. Solution To find the -intercept, substitute for and solve for. 7 Write original equation. 7 () Substitute for. } 7 Solve for. To find the -intercept, substitute for and solve for. Copright b McDougal Littell, a division of Houghton Miffl in Compan. EXAMPLE 7 Write original equation. 7() Substitute for. } 7 Solve for. The -intercept is. The -intercept is 7. Use a graph to find the intercepts Identif the -intercept and -intercept of the graph. Solution To find the -intercept, look to see where the graph crosses the -ais. The -intercept is. To find the -intercept, look to see where the graph crosses the -ais. The -intercept is. 4. Algebra 9

10 4. Stud Guide continued For use with pages EXAMPLE Use intercepts to graph an equation Graph. Label the points where the line crosses the ais. Solution STEP Find the intercepts. () () -intercept -intercept STEP Plot the points that correspond to the intercepts. The -intercept is, so plot and label the point (, ). The -intercept is, so plot and label the point (, ). STEP Connect the points b drawing a line through them. (, ) (, ) CHECK You can check the graph of the equation b using a third point. When 4,, so the ordered pair (4, ) is a third solution of the equation. You can see that (4, ) lies on the graph, so the graph is correct. Eercises for Eamples,, and Find the -intercept and the -intercept of the graph of the equation } 4. Graph }. Label the point where the line crosses the ais.. Identif the -intercept and -intercept of the graph Copright b McDougal Littell, a division of Houghton Miffl in Compan. 4 Algebra