 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| What To Do About Integers, What Are They? How To Use Them....THIS IS YOUR STUDY GUIDE!!! |
|
|
|
Integers are positive and negative whole numbers. That is it. They are simply numbers. When you are asked to write aqn integer for a situation, you simply write a number that would work for the situation,
EX:
Write an integer for the following situations:
a) A gain of 15 pounds +15
b) A decrease of 45 $ -45
c) Positive 456 +456
d) A loss of 56 points +56
e) A deposit of $12.36 +$12.36
|
|
|
|
Sometimes you will be asked to PLOT a point on a number line. All you have to do is draw a numberline -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 and put a dot, dot rhymes with plot on the number line. Of course, the number line you draw should look a little different than this, I just can't do it exact using this progam. DO NOT USE ARROWS TO "PLOT" THE POINTS!!!! |
|
|
|
Opposites are really easy. If you are given a positive, the opposite is a neagtive of that number and vice versa.
EX:
-2 +2
90 -90
123 -123
-98 + 98 |
|
|
|
Absolute Value is when the integer is in the little house looking thing. There is a vertical line on either side of the number. The answer to absolute value is always POSITIVE. Absoulte value means how far an integer is from zero on a number line. It is NOT the same thing as an opposite.
EX:
What is the absolute value?
56 56
-78 78
-123 123
97 97
|
|
|
|
You will be asked to order and compare integers using greater than ,less than, and equal to. Be familiar with how the numbers would look on a number line.
EX
90>89
-8<-5
-45>-55
EX
Order the integers.
-9, -5, -12, 2, 0, -45, 89
-45, -12, -9, -5, 0, 2, 89
|
|
|
|
RULES FOR ADDING AND SUBTRACTING INTEGERS- You should probably memorize them....YES DO IT! Remember the dots and counting on the number line.
1) When you have a positive and a positive, you add and the answer is positive(first grade math).
7+8=15 8+10=18 56+50=106 7+90= 97 4+9= 13
2) When you have two negative numbers, you add and the answer is negative.
-8-90=-89 -5-6=-11 -45-45=-90 -34-2-=-36 -100-45=-145
3) When you have a negative and a positive number, you subtract and your answer is the sign of the bigger number.
-3+2=-1 -45+40=-5 -2+4=2 4-8= -4 34-40=-6
4) When you have two negatives SIGNS in a row they become a positive.
9--8=17 8-(-7)=15 5-(-45)=50 -12-(-8)=-4 -60--70=10
|
|
|
|
RULES FOR MULTIPLYING AND DIVIDING INTEGERS- Memorize them! You multiply and divide just like you learned to in 4th grade. Nothing has changed. You just need to know what sign to use for your answer.
1) When you multiply or divide two positive numbers, your answer is positive.
4x5=20 90/9=10 7x7=49 60/20=3 120/2=60
2) When you multiply or divide two negative numbers, your answer is postive.
-2x-3=6 -4x-30=120 -90/-9=10 -10/-2= 5 -9/-3=3
3) When you multiply or divide a negative and a postive in any order, your answer is negative.
9/-3=-3 -10x5=-50 -4x5=-20 6x-6=-36 -20/2=-10
**The general rule to follow here is an even number of negatives means your answer will be positive, and an odd number will be negative.**
-2x-2x-2= -8 (there are 3 negatives, 3 is odd, your answer is negative)
7x -1x-1= 7 (there are two negatives, 2 is even, your answer is positive)
|
|
|
|
You can certainly model the following situations with dots and number lines, but at this point, you should only use these as a reference. It will be most valuable to you to memorize and learn the rules to know what to do in each situation. |
|