Describe in detail how you would create a number line with the following points: 3, 2.25, the opposite of 4, and – (–1 1/2).

First, I would create a number line that includes the number -4 to 4, with 1/4 notches (3 notches between each number). 

For 3, I would count 3 numbers to the right from zero. 

For 2.25, I would count 2 numbers from zero, plus one additional notch to the right. Remember that each notch represents 1/4, or 0.25. 

For the opposite of 4, I would count 4 to the left to -4. The opposite of 4 is -4. 

For -(-1 1/2), I would remember that this number is actually 1 1/2, since a negative times a negative number is positive. I would count one number to the right of zero, plus two notches. 

Subtracting is the opposite of adding