An airplane has a total of 152 seats. The number of coach-class seats is 5 more than six times the number of first-class seats. How many of each type of seat are there on the plane?

After hours of algebra homework, my brain seems fried! This is suppose to be solved using substition. Can anybody help me with this? Once I see how, Im sure I'll say duuhhhh.

THank You in advance!!

Todd