if there are 310 wheels on a parking lot and there parks both motorcuckles and cars there, how many cars and motorcyckles have parked there

Let x be the number of motorcycles and y be the number of cars...each car has 4 wheels and each motorcycle has 2...so we have

4x + 2y = 310    we have more variables than equations, so there will be multiple integer solutions

Here's a graph of all the possibilities......https://www.desmos.com/calculator/wsaqqgkn4p

Some are (4, 147), (10, 135), (22. 111), (40, 75)....etc.