well this is how i would solve that. You know larry has 14 cars. so write that.
Larry=14 cars
Now you don't know how much his grandparents gave him so write that.
grandparents= x amount of cars
Now you know the total amount larry has. so write that.
total of cars=22
Now, this is how i would solve a question like this. i would take the numbers i have and turn it into an addition problem. so it will look like the following.
14+x=22
now it is easy to solve from here. If you subtract 14 on both sides you will see how many cars his grandparents gave.
14+x+22
-14
------------
x=8
and if u wanna check it. all u do is add 8 to 14 and see if it gives you 22. That's it!!