**When you have finished this page,
try the Adding and Subtracting of Positive and
Negative Numbers Quiz.**

**When one thinks about adding and
subtracting numbers, it is really the act of combining numbers or the amounts
they represent. To see how closely they are related. let's look at some examples
and perhaps challenge some beliefs you may have about both processes. **

**In the first example, the ball moves
from zero start point to two and then moves down three more to the number five.
**

**I **

**In the next example, we see a traditional
subtraction problem. The ball is at the starting point of zero and then goes
to five and then back three places as indicated by the minus sign. The stopping
point is the number two.**

**The next example is quite unlike
any other problem - both numbers on the left side of the equation have minus
signs - they are both negative numbers. From the zero starting point, the first
number goes three places to the left on the negative side of the number line
and then two more places further to the left to the number five place. While
this looks like a subtraction problem, it also seems like an addition problem
- of negative numbers. Thus, one can see how closely addition and subtraction
are - they are merely the combining of positive and negative numbers. **

**If we look at the next equation,
we see that it is very much like the subtraction problem in the second example,
but written with the first two numbers in reverse, Again, it is the process
of combining the numbers rather than strictly adding or strictly subtracting
the numbers. The ball begins at the zero start point and goes to the left a
negative three places. It then goes right from the negative three place five
places and stops at the two place on the right side of the number line. **