Unit+2

= Unit 2 =

In Unit 2 we started talking about Operations in Algebra.

We began with an overview of how numbers were organized. Some people like to think of the Real Number System as looking like this.



Here are the notes we took on the Real Number system and ordering numbers. We used a filing system on our computers to show exactly the same thing. After reviewing the Real number system I gave you a worksheet to complete in class. Here's that worksheet.

In this unit we also began talking about absolute value. I even gave you a few equations with absolute value to learn how to graph. Remember that absolute value literally means the distance away from zero on the number line. Here are the notes we took on the Absolute value.

In sections 2.2-2.4, we reviewed adding, subtracting, multiplying, and dividing integers. We also talked a little about two properties of numbers: the Identity Property of Addition and the Additive Inverse Property. Here are the notes for these sections.

Before we continued on with book work, we took a short detour and began an in-class long-term activity. We set up a spreadsheet to show the growth (or fall) of two stocks on the NYSE. I picked Coca-cola and Yahoo! as my two companies. You got to pick any two you wanted. We've been following our stocks daily to find the current trading price so that we could put that amount into our spreadsheet. I showed people how to set up a formula in the spreadsheet cells so that you don't have to do all the calculations and the software will do it for you.

Section 2.5 talked about the different properties of addition and multiplication. We got into groups and made posters representing each one. Here are the ones that we did. 1. **Commutative Property** (Note: commutative, not communative) a+b+c=b+a+c 2. **Associative Property** (a+b)+c=a+(b+c) 3. **Distributive Property** (Probably the one you'll see the most in Algebra) a(b+c)=ab+ac or a(b-c)=ab-ac 4. **Closure Property** (maybe the hardest to understand) A set is said to be closed under some operation, if, and only if, the performance of that operation __always__ produces a result in that set. Here's what I mean. (Even #)+(Even #)=(Even #). That **always** happens so "Even numbers are closed under addition." 5. **Transitive Property** If a>b, and b>c, then a>c 6. **The Identity Property** a+0=a or a*1=a

Sections 2.6 and 2.7 were about Adding/Subtracting and Multiplying/Dividing Expressions. Remember that an expression is a combination of numbers, variables and operations. Here are the notes for those two sections.

Here is the practice test that might help you with your test.

Here is the link to Courtney's blog about the distributive property. [|mathq1projectdistributiveproperty.blogspot.com]