02 February 2006

Homework for 2/3 february

Chapter 7.1

#1-9 odd, 10, 11-27 odd, and worksheet:

Algebra 1 slopes/lines worksheet 2/3 February

1) Given the line y=.5x+6,write an equation for the line through the origin that has
the same slope. Write an equation for the line through (2,−4) that has the same slope.

2) At noon, my odometer read 6852 miles. At 3:30 pm, it read 7034 miles.
(a) What was my average rate of change (speed) during these three and a half hours?
(b) Let t represent the number of hours I have been driving since noon and y represent
my odometer reading. Write an equation that relates y and t.
(c) Graph your equation.
(d) Show that the point (5,7112) is on your line, and then interpret this point in the
context of this problem.

3) What is the slope between (3, 7) and (5, 4)? (5, 4) and (3, 7)? (a, b) and (c, d)? (c, d)
and (a, b)?

4) Avery’s long-distance phone company charges a connect fee in addition to a per-minute charge for each call. Avery’s most recent bill included a $4.24 charge for a 12-minute call and a $6.00 charge for a 20-minute call.
(a) What is the per-minute charge?
(b) What is the connect fee?
(c) How much would Avery be billed for a five-minute call?
(d) How much would Avery be charged for a call m minutes long?
(e) Avery was able to figure out answers to (a) and (b) without doing any algebra. How?

5) (Continuation) I was recently called by a telemarketer asking me to change my longdistance phone company. This new company charges $0.33 per minute with no connect fee. Is this a better deal than the company described in the previous problem? Show evidence.

6) The point (3, 2) is on the line y = 2x + b. Find the value of b. Graph the line.

7) Graph the line y = 4x + 6, and find
(a) the y-coordinate of the point on the line whose x-coordinate is 2;
(b) the x-coordinate of the point on the line whose y-coordinate is 2.

8) A toy manufacturer is going to produce a new toy car. Each one costs $3 to make, and the company will also have to spend $200 to set up the machinery to make them.
(a) What will it cost to produce the first hundred cars? the first n cars?
(b) The company sells the cars for $4 each. Thus the company takes in $400 by selling
one hundred cars. How much money does the company take in by selling n cars?
(c) How many cars does the company need to make and sell in order to make a profit?