I have error undefined console. Thanks you.

Question

Undefined console.
https://code.sololearn.com/W2C8IWM7kSsH/?ref=app

Answer 1

A function should return a value before output can obtain the value.

return car.mileage += miles;

Answer 2

Missing return statement.

drive: function (miles) {
return car.mileage += miles;
}

Answer 3

Because the drive function aren't returning anything.That's why printing the function will become undefined.If you want to return the car.mileage, use
return car.mileage;
Here is the solution:
https://code.sololearn.com/WA23A18A0A19