Homework for 6/7 february

Chapter 7.2

#1-13

and worksheet:

Algebra 1 Worksheet February 6/7 2006

1. Substitute 4-3x for y. Then rewrite each expression in terms of one variable.

a) 5x+2y b) 7x-2y

Check that each ordered pair is a solution to each system. If the pair is not a solution point, explain why not.

2. (2, 5) 3. (-2, 34)

y=x+3 y=38-2x
y=2x-1 y=-21-0.5x

Solve each system of equations by substitution, and check your solution:

4. y=25+30x 5. y=4-3x
y=15+32x y=2x-1

6. Explain the difference between a line that has no slope and a line whose slope is zero.

7. Chris does a lot of babysitting. When parents drop off their children and Chris can supervise at home, the hourly rate is $3. If Chris has to travel to the child’s home, there is a fixed charge of $5 for transportation in addition to the $3 hourly rate.
a) Graph y = 3x and y = 3x + 5. What do these lines have to do with the babysitting
context? What feature do they have in common? How do they differ?
(b)Predict what the graph of y = 3x + 6 will look like. What change in the babysitting
context does this line suggest?

8. The diagram shows two steel rods hinged at one end. The other end is connected by a
bungee cord (the dotted segment), whose unstretched length is 10 inches. The rods are 5 inches and 18 inches long. Use inequality symbols to describe all the possible lengths for the bungee cord, which stays attached at both ends while it is being stretched.