Systems of linear equations i really dont know how to do this : ')

Me. i can't figure out this question. give an explanation too. .

Another type of subtraction equation is 16-b=7. explain how you would sole this equation then solve it.

Raymond just got done jumping at super bounce trampoline center. the total cost of his session was $43.25 . he had to pay a $7 entrance fee and $1.25 for every minute he was on the trampoline. write an equation to determine the number of minutes (t) that raymond was on the trampoline.