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The absolute value of a number is its non-negative value. For example:

As you can see, when absolute value is applied to a negative number such as –3, the minus sign is dropped. Otherwise, absolute value has no effect on non-negative numbers such as 5 and 0.

When evaluating an absolute value, evaluate the expression inside the absolute value bars, then apply the absolute value, and then evaluate the rest of the expression. For example:

Which of the following is equivalent to ?

(A) –13

(B) –7

(C) 7

(D) 13

To begin, simplify the two expressions inside the absolute value bars:

Next, substitute and :

Now complete the problem:

Therefore, Answer B is correct.