March 11th - Investigation 2.2 and 2.3

Today we continued to look at integers and specifically subtracting integers.

We worked with the following number sets:

-8 - -3 =

8 -3 =

8 - -3 =

-8 - 3 =

-3 - -8 =

The following were the rules/ algorithms we came up with.

1. You will get a positive number if the number you start with is greater than the number you subtract it from.

2. If the first number is less than the second number then the difference will be negative.

Another student then said:
3. If the first number is greater than the second then the difference will be positive.

We had good discussions and a good use of the chip model today.

Here is an interactive link to chip models. 
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