Grade 7 Integer Review
Eg. (4, -4) are integers. (10, -10), ( 100, -100), ( 3, -3) are all examples
Zero pairs can be used to solve math problems with both positive and negative numbers in them.
Zero pairs can be represented by using different coloured chips. Commonly blue represents negative and red represents positive. Let's use zero pairs to solve the first starred homework question.
1) -3 - (-7) = 4
In this question you need to use Isfeld's rhyme " When subtracting something that isn't there use a zero pair." You make the zero pair for -7 and you remove -7 so all you have left is +7. You then just make zero pairs using the 3 blue chips and you have 4 positive chips left.
2) -3 - 7 = -10
For this one you have to make a zero pair so you can take away +7. You then combine negative 3 and negative 7 to get -10.
3) 3 - 7 = -4
You should use zero pairs for this because it makes it easier to understand. Make a zero pair for 7. Remove the positive part. Now make zero pairs with the three positve chips. You should have -4 remaining.
4) 3 + 7 = 10
This one is kind of obvious but let's use chips to figure it out. You should get 10.
5) -3 + 7 = 4
This one is pretty straight forward. Make zero pairs out of the 3 negative chips and you should have 4 left over.
This question is asking you "how do you share (-6) with 2 groups?"
D) 6/(-2) = -3
For this question you must use multiplicative inverse to get the answer.
The multiplicative inverse of this question is (-2) x _ = 6. The answer to the newly inversed question is positive. That means that both of the factors are negative. That means that the blank is -3 because the answer is positive and one of the factors (-2) is already negative.
When there is one negative sign or an odd number of negative signs the quotient is negative.
Order of Operations with Integers
(+5) x (-3) + (-6)/(+3) =
We must use BEDMAS to solve this problem. To help us do that you should put square bracket around multiplication or division parts. The question should look like this.
[ (+5) x (-3) ] + [ (-6)/(+3) ]
(-15) + [ (-6)/(+3) ]
(-15) + (-2)