Subtract from .

The absolute value is the distance between a number and zero. The distance between and is .

Simplify the numerator.

Add and .

The absolute value is the distance between a number and zero. The distance between and is .

Cancel the common factor of and .

Factor out of .

Cancel the common factors.

Factor out of .

Cancel the common factor.

Rewrite the expression.

To write as a fraction with a common denominator, multiply by .

Multiply and .

Multiply by .

Combine the numerators over the common denominator.

Multiply by .

Subtract from .

Move the negative in front of the fraction.

The result can be shown in multiple forms.

Exact Form:

Decimal Form:

Evaluate (|15-12|)/4-(|-21+9|)/8