Is the following graph a linear function, nonlinear function, and/or a relation

Use set buikder notation to represent the following set: {, -2, -1, 0}

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.

∆red ≅ ∆ by rule will give brainiest if possible