Suppose you have a bag with an unknown number of blocks and you take 3 blocks out of the bag. Then you put the bag in one pan of a pan balance. it takes 7 blocks in the other pan to make the bags in the other pan to make the pans hang evenly. How many blocks were in the bag before you took 3 out
x - 3
On the left-hand side of the balance, what does x represent on the bag?