## Monday, March 7, 2011

### Meldrick's Great Big Book of Integers

Chapter 1

Integers can be represented by-

number lines
OR
integer chips

Integers are any positive or negative whole numbers - 0 is also an integer even it isn't positive or negative.
When a positive integer and a negative integer of the same value are put together, they form a zero pair - the value of any number of zero pairs is zero.
Here is a useful song to remember -

when subtracting something that isn't there, use a zero pair

Grade 7 integer questions are written like this -
(+4)+(-4)

Standard form (grade 9) integer questions are written like this -
4-4

-3 - (-7)

-3 - 7

3 - 7

3 + 7

-3 + 7

Chapter 2
Multiplying Integers

The sign rule says that if you are multiplying or dividing integers, you multiply/divide first, then count the amount of negative signs. If the amount is even, the product/quotient will be positive. If the amount is odd, the product/quotient will be negative.

(+2)*(+3)

(+2)*(-3)

(-2)*(+3)

(-2)*(-3)

Chapter 3

Dividing Integers

Partative division is when you make groups of your total to get your answer. It is usually shown on a number line.

Quotative division is when you share your total with groups. However, not all integer questions can be represented by quotative division... yet.

You can also use multiplicative inverse to get the quotient of a division question -

6/(-2) = -3
(-3)*(-2) = 6
(-2)*(-3) = 6

If you remember the sign rule earlier, you can solve these questions -

6/2 = 3
*there are no negative signs - the answer is positive*

-6/(-2) = 3
*there is an even number of negative signs - the answer is positive*

-6/2 = -3
*there is an odd number of negative signs - the answer is negative*

6/-2 = -3
*there is an odd number of negative signs - the answer is negative*

Chapter 4
Order of Operations

Do you remember BEDMAS? If not...

Brackets
Exponents
Division
Multiplication
Subtraction

Not that you will ever see exponents in an integer question... but the rest is very important.

EX.

5*3+(-6)/3