Operations with absolute value

Definition

The absolute value of a number a is denoted as |a|

|a| = a, if a is positive

|a| = a, if a is negative

|0| = 0

Absolute value of a number is the distance of the number on the number line from 0. The absolute value of a number is never negative.

For example, the absolute value of both 5 and 5 is 5. The absolute value of 0 is 0.

Finding absolute value of a number is like removing any negative sign in front of a number, and considering all numbers as positive.

In this lesson, we solve problems involving operations with absolute values.

Example 1

Evaluate the following

|13 19| |11|

Solution

Step 1:

Simplifying

|13 19| |11| = |6| 11 = 6 11

Step 2:

It is a subtraction of integers problem

The signs are different. So, we take the difference of absolute values

|11| |6| = 11 6 = 5

Step 3:

The sign of the numbers with larger absolute value (11) is .

We keep this sign with the difference obtained in above step

So, |13 19| |11| = 5

Example 2

Evaluate the following

|7 23| |6|

Solution

Step 1:

Simplifying

|7 23| |6| = |16| 6 = 16 6

Step 2:

It is a subtraction of integers problem

The signs are different. So, we take the difference of absolute values

|16| |6| = 16 6 = 10

Step 3:

The sign of the numbers with larger absolute value (16) is +.

We keep this sign with the difference obtained in above step

So, |7 23| |6| = + 10