Acc. Alg. II W.S. Sec Assign. # 5. Show work to justify all answers!!!!!!!

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1 Acc. Alg. II W.S. Sec Assign. # 5 Name Show work to justify all answers!!!!!!! 1. Determine p so that the slope of the line containing this pair of points has the given value. 5 ( -2, p), (4, -p); m = Find the slope of the line that contains the pair of points ( d, b), (d + e, e).. Consider the following equations. Tell which equation does NOT belong in the group and why. A. y = 5x + B. 2x + = 5y 9 + 4x C. x 5y + 9 = 0 D. ( x + 9) = 4y 7 4. In 1990, 8.5% of the doctorates in engineering were awarded to women. By 2002, 11.5% were earned by women. Find the average rate of change in the percent of engineering doctorates earned by women form 1990 to At 10:00 a.m., you are 150 miles from home. At 4:00 p.m., you are 90 miles from home. Find your average speed. (Assume you are traveling directly away form home.) 6. From 1990 through 2001, the number of magazines published in the United States increased at an approximately linear rate. In 1990, 1456 magazines were published and in 2001, Write a linear model for the number of magazines being published. (Hint: Let t = 0 represent 1990.) How many would you expect to be published in 2005?

2 Acc. Alg. II W.S. Sec #2 page 2 7. Mr. Henderson is a repair person who charges a fee for coming to your house, plus an hourly rate. He charges Mrs. Smith $175 for a repair that took 7 hours and Mrs. Jones $65 for a repair that took hours. Write a linear model for repair charges. How much will Mr. Henderson charge for repairs that take 5 hours? 8. Reggie has two pay receipts showing that he earned $72 for 12 hours work one week and $10.50 for 18 hours worked another week. A. Express Reggie s pay as a linear equation in the slope intercept form. B. What is Reggie s hourly rate of pay? C. What interpretation can you give for the y-intercept? 9. Find the slope of the line through the points 1, 2 2 and 2 1,. 10. Write in standard form an equation of the line with slope = -1/2 through the point (8, -1). 11. Write in point-slope form the equation of the line through (-2, 1) and (-10, 17).

3 Acc. Alg. II W.S. Sec #2 page 12. Write the equation of a line in slope-intercept form through (1, 9) and (6, 2). 1. Write an equation of the line, in slope-intercept form, through (6, 1) and perpendicular to x 4y = If the graph of the equation ax + 2y = 8 is perpendicular to the graph of the equation 2x + y =, find the value of a. 15. You are buying a $2175 surround sound stereo system on layaway. You make a $200 deposit and then make weekly payments according to the equation a = t where a is the amount you owe and t is the number of weeks. A. What is the original amount you owe on layaway? B. What is your weekly payment? 16. Suppose that you work part-time at a department store, earning a base salary of $50 per week plus a 15% commission on all sales that you make. A. Write a linear equation to represent the relationship between the weekly sales and the weekly income. Remember your variable key. B. If your weekly income is $20. What are your weekly sales?

4 Acc. Alg. II W.S. Sec #2 page The law of supply states that the quantity supplied of an item varies directly with the price of that item. Suppose that for $4 per tape 5 million cassette tapes will be supplied. Write an equation that relates the number c (in millions) of cassette tapes supplied to the price p (in dollars) of the tapes. Then determine how many cassette tapes will be supplied for $5 per tape. 18. The number of calories, C, a person burns performing an activity varies directly with the time t (in minutes) the person spends performing the activity. A 160 pound person can burn 7 calories by dancing for 20 minutes. How long should a 160 pound person dance to burn 48 calories? Solve each proportion for the variable. 19. Solve a 2 2 a 2(p 2) ( p 1) = for a. 20. Solve = for p Graph 1 x + y = Find the x-intercept and y-intercept for the 4 6 linear equation 4x y = Name a point on the graph of y 5 = ( x + 2) and then give the slope of the line, the x-intercept and y-intercept. Point: x-int: Slope: y-int:

5 Acc. Alg. II W.S. Sec #2 page 5 Answers: Remember, I do not guarantee my answers. Ask questions if you don t agree y = x b e e 14. a = -1. B is the only line with a negative slope 15. A) $1975 B) $ ¼ of a percent 16. A) I =.15s + 50 B) $ mph million cassettes 6. y = 120t ; 256 magazines minutes 7. y = 27.5x 17.5; $ A) y = 9.75x -45 B) $9.75 C) Possible ans: $45 in taxes are deducted from Reggie s paycheck a = p = The points (-2, 2) & (7, -2) should be on your graph x + y = 22. x-int = 2 y-int = y 1 = 2( x + 2) or y 17 = 2( x + 10) y = x Pt. (-2, 5) m = - x-int = 1 y-int = -1