A plumber uses the expression 75+50h to determine how many dollars to charge for a job that lasts h hours. If a plumber job lasts 5 hours (h=5) how many would the plumber charge?
You replace 'h' with '5'. So you're left with 75+50(5). Since multiplication comes before addition in the mathematical process, you multiply 50x5 first and add its product to 75.
