How do these functions differ from functions you have used in algebra in the past

What is the rotational symmetry of a wheel

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.

Give me the equations of two lines that have the same slope but are not parallel.