Math Final

Hello all. Just wanted to give you a run-down of what's going to be on your final. Remember, we'll be taking a practice final next week as we review.

Please review the following in your notes (also, remember to use Glencoe's online Self-Check Quizzes to test your knowledge of each section in the book):

- Prime factorization
- Powers and exponents
- Order of operations
- Variables and expressions
- Area

- Graphing (Bar/Line graphs)
- Frequency tables & Stem and Leaf plots
- Measures of central tendency (Mean, Median, Mode, Range)

- Rounding, adding, subtracting, multiplying, and dividing decimals

- Adding, subtracting, multiplying, and dividing fractions
- GCF/LCM
- Turning fractions into decimals
- Turning decimals into fractions

- Comparing/ordering fractions and decimals

- Adding, subtracting, multiplying, and dividing integers
- The Coordinate Plane

Adding Integers

Hello all,
Just wanted to post a quick review for your assessment Tuesday. We'll be checking the practice quiz Monday so please remember to bring it with you to class for workshop.

On this assessment, we'll be covering 8-1 through 8-3 (adding/subtracting integers). For subtraction, please review the previous post about the KFC method. Remember, Keep, Flip, Change!!! :)

For addition:

First, remember that a negative plus a negative will always equal a negative. If you lose five bucks and then you lose three more, you've LOST a total of 8 bucks, and a loss is represented by a negative, so you'd have -8 dollars.

-5 + -3 = -8

The tricky part comes in when you need to add a negative and a positive together.

Let's review the 3 methods we can use to add negative and positive integers:

1. Use a number line. From your starting point, move to the right if adding a positive integer; move to the left if adding a negative integer.

2. Use the method you have in your notes:
     1. Ignore the signs. What numbers do you have?
     2. Find the difference of those two numbers.
     3. For your answer, keep the sign of the biggest number.
     
     -7 + 4 -----> What numbers do I have if I ignore the signs? 7 and 4.
       7 - 4 ----->  Now, I take the difference of the two numbers.
       = 3   -----> Since the number with the greatest absolute value was -7, the answer becomes negative.
       = - 3

3. Use counters! Place negative and positive symbols inside a shape of your choosing. Cancel out whatever you can. What you're left with is your answer. Example:

The following picture represents 4 + (-5):

Since 1 positive is cancelled out by one negative, we are left with this, which represents -1:

And voila! You have your answer :)

If you're having a hard time adding integers in your head, any of these 3 methods will help you out. Happy adding!

Subtraction and... Fried Chicken?!!

Scared of subtraction involving negative integers? Don't be - remember, it's just addition in disguise!

The rule for subtraction is:

Add the OpPoSiTe!


Who likes fried chicken? It's one of my all-time favorites. :)

Img: thebittenword.com

So... what does fried chicken have to do with subtracting integers? Check out this cool chart from passyworldofmathematics.com:


Then, solve your problem as an addition problem. Here are a few examples:

-5 - 3 = ?
-5 + (-3) = -8  ---> Both numbers are the same sign, so we can add like normal and keep the sign.

7 - (-2) = ?
7 + 2 = 9   ---> Again, both numbers are the same sign, so we can add like normal and keep the sign.

4 - 8 = ?
4 + (-8) = ?  ---> Now we've got addition with two different signs, so remember to use your absolute values!
The absolute values are 4 and 8. The difference between 4 and 8 is 4. Now, is it negative or positive? Look at the original number that had the greatest absolute value: -8. Since it's negative, we know the answer is -4.



1) a. -5
    b. -1
    c. -3

2) a. -4
    b. -6
    c. 5

3) a. 35
    b. -106
    c. -46

HaPpY SuBtRaCtInG!