# How do you write the mathematical expression for "the difference of 7 and a number n"?

May 14, 2018

$| 7 - n | = \text{ positive difference}$

If you wish to indicate if n is less than or greater then 7 then you do this: $7 - n$

#### Explanation:

If $n > 7$ then we have $n - 7$ which is positive

If $n < 7$ then we have $7 - n$ which is also positive.

So how do we end up with a positive answer no matter what the value of $n$ is.

WE DO THIS:

$| 7 - n | = \text{ positive difference}$