This is a basic subtraction problem :-).
You will subtract how much money the mechanic gives to the supplier; which in this case will be $20, by the total amount of the parts which is $14.56.
20-14.56 = 5.44
Therefore, he will receive $5.44 in change for the transaction.
Example:
Linear absolute value inequalities all have a similar equation of |ax + b| < c, except they can be less than, greater than, less than or equal to, or greater than or equal to.
Hope this helped :)
