Let x represent the number of hours that Justin works in a week.
Let y represent the total amount that Justin would receive for working for x hours.
Justin earns $8 an hour for the first 40 hours he works and $12 for each additional hour. This means that the total amount that he earns in a week would be
y = 8×40 + 12(x - 40)
y = 320 + 12(x - 40)
If he earns 48 hours in a week, the total amount that he earned would be
