## Subtraction as Distance

## Formative Assessment

# Summary of the Math: Subtraction as Distance

**Read and Discuss**

Subtraction can be looked at as the distance between two numbers.

You can use the number line to model the subtraction *a* − *b* as distance, where *a* and *b* are any two numbers (positive or negative), as follows.

- Locate points
*a*and*b*. - Find the distance between points
*a*and*b.*This value will be a positive number, because a distance is always positive. - Determine the sign of the distance value in order to find the answer to the subtraction problem. The value of
*a − b*is:- Positive if
*a > b*(if*a*is to the right of*b*on the number line). - Negative if
*a < b*(if*a*is to the left of*b*on the number line).

- Positive if

## Hint:

Can you:

- Explain the method for subtracting integers by finding the distance between two points on a number line?