Homework due Tuesday 11/1

• On the handout "More Linear Programming Problems" from Friday's class, do problems 1-3.
  
• Also do Lesson 3.5 problems 33-37.
  

Keep using graph paper for all graphs.

Homework due Friday 10/28

• On the handout "Linear Programming" from Wednesday's class, do problems 1-3.
  
• Also do Lesson 3.5 problems 11, 15, 23, 27, 31, and 32.
  

Keep using graph paper for all graphs.

Homework due Wednesday 10/26

Lesson 3.4 exercises 8, 13, 17, 19, 21, 27, 33-36, 37, 41, 43, 45, 46, 48-52.



Also: The deadline for making up the homework due Wednesday 10/19 (post a linear system word problem to FirstClass) is Friday 10/28. If you're still having trouble completing that assignment, see me outside class.

Homework due Tuesday 10/25

If not already done, finish the class sheet on graphing inequalities.



Then do Lesson 3.3 exercises 15, 23, 27, 29, 30, 31, 37, 39, 43, 44, 45, 52, 53. Use graph paper for all graphs.

Homework due Monday 10/24

This assignment is a review of one-variable inequalities.

• Lesson 1.7 problems 13, 23, 29, 31, 43-51 odd, 59-65 odd.
  
• Lesson 1.8 problems 19-24, 25, 29, 33, 41, 43, 47, 58-60.
  

Test Friday 10/21

We will have a test Friday 10/21 on linear systems (graphical, algebraic, and matrix solving methods). The relevant textbook sections are 3.1, 3.2, and 4.5; we also had some work outside the textbook (such as 3-variable elimination problems).



Note: I'll be available for extra help after school Wednesday but not on Thursday, so plan ahead if you're expecting to seek help.

Alternate location to download FirstClass

I've heard from some of you about error messages when trying to download the FirstClass software from the school server. I suspect the system is getting overloaded from too many users trying at once.



Here's an alternate source that you can use instead:

http://www.firstclass.com/ClientDownloads/

It's the same software, just obtained directly from the publisher instead
of the school computer.

Homework due Wednesday 10/19

• If you had trouble last night, try again on Lesson 4.5 exercises 31-36.
  
• Do the set of application problems from today's handout (problems 2-7).
  
• Problem 7 asks you to log into FirstClass and post an answer. If you want to do this from home (recommended if you are able), download the software from here or
  here. (It's the same program from both places; the first address seems to be getting overloaded and having problems; the second link shouldn't have this problem.)
  

Homework due Tuesday 10/18

Here's the link to the applet for today's computer lab: Matrix Row Operations Tool.



The homework is:

• Complete the computer lab, if not finished during class. It will be collected on Tuesday.
  
• Read the textbook from p. 254 to the middle of p. 255. Use your calculator to do all three examples. (For calculator key hints: p. 268 example 3 for how to type in a matrix; p. 271 for the rref command that gives the reduced matrix.)
  
• Use your calculator to do Lesson 4.5 exercises 31-36.
  

Homework due Monday 10/17

Lesson 4.5 exercises 1, 3, 4, 9, 11, 12, 19-29 odd.

No homework due Friday 10/14

Holiday - no homework.

Homework due Wednesday 10/12

From today's class handout "Systems of Linear Equations with Three or More Variables" do problems 1-13 odd.

Homework due Tuesday 10/11

Lesson 3.1 Exercises

• Using graphing method on graph paper: 15, 19, 23
  
• Using substitution method: 27, 31, 37, 41, 43
  
• Using graphing method on calculator: 47, 49
  

Lesson 3.2 Exercises

• Using elimination method: 11, 15, 19, 21, 23, 25
  
• Using your choice of method: 27, 31, 35, 40, 43–46
  

Finally, do this: Did you find any problems where the solution method did not lead to a single solution? Write an explanation in your own words of what happened differently in those problems. (Why did the methods that worked in other problems not work? What happened instead?)

Optional extra on LinReg and crickets

As a follow-up to Wednesday's linear regression problem about cricket chirp rates, I think the following extra activity will interest some of you. And even if you only have a few minutes to spend, I think you'll get something out of it.



On this web page read at least the first two sections about crickets and linear modeling.



You'll see a linear model similar to the class problem, but note these changes: the x and y variables are reversed; the chirp rates are per-minute rather than per-second; and the data is different enough that it's probably from a different species of cricket from the class problem.



A few cool things about the story on the linked web page:

• One researcher (Dolbert) had proposed a certain linear equation as the model, but then other researchers (Bessey) used recorded data and linear regression to get a more accurate equation.
  
• The page includes an applet where you can control the slope and intercept using sliders, to make your own best guess of the best fit line. This is pretty fun to play with -- try it yourself! (If it's not working on your computer, make sure your browser has Java applets enabled. Also, if you have a slow connection, it might take some time to load.)
  
• The page asks good questions about the domain: for what temperatures does the equation provide a realistic model? Identifying the realistic domain is always an important part of doing linear modeling and regression.
  

If you try this activity, please let me know what you think of it, OK? That will help decide whether to have the whole class try it next year.

Homework due Friday 10/7

In class we started these problems; the homework is to finish them:

• two problems on this handout: "More modeling using best-fit lines"
  
• Lesson 1.5 problems 24 and 25
  

Books are not needed for class on Friday.

No homework for Wednesday 10/5

We did these problems during class on Monday 10/3: Lesson 1.5 exercises 15-20 and 22b.



Due to the holiday, there's no homework due Wednesday.