What is the total price of a $40 item including 6.5% sales tax

What is the inverse of the function f(x)=2x+1

Elena and her husband marc both drive to work. elena's car has a current mileage (total distance driven) of 15,000 and she drives 23,000 miles more each year. marc's car has a current mileage of 46,000 and he drives 9,000 miles more each year. will the mileages for the two cars ever be equal? explain.

This is about circle theorems. someone asap : (