Question

Andrew makes $6 an hour plus $9 an hour for every hour of overtime. Overtime hours are any hours more than 40 hours for the week.
Part A: Create an equation that shows the amount of wages earned, W, for working x hours in a week when there is no overtime.

Part B: Create an equation that shows the amount of wages earned, S, for working y hours of overtime. Hint: Remember to include in the equation the amount earned from working 40 hours.

Part C: Andrew earned $330 in 1 week. How many hours (regular plus overtime) did he work?

Answer 1

Part A: W = 6x 

Part B: Since without overtime it is 6 $ per hour and you need to make 40 hours 
you would multiply 6 *40 = 240
So S = 240 + 9y

Part C: Substitute
Since Andrew earned 330 you would substitute it for S 

330 = 240 + 9y <--- solve for y

330  ( - 240 ) = 240 ( - 240 ) 9y  < ---- subtract 240 from each side 
90 = 9y 
90 / 9 = 9y / 9 <----- divide by 9 

10 =y   Andrew worked 10 hours for overtime  

Check  

330 = 240 + 9(10)
330 = 240 + 90 
330 = 330 <-- your answer is 10