Tom sells cellphones for $45 a phone. Sam sells tablets for $149 a tablet but he is not making any profit yet because he still needs to pay off his order of $4992. when will the two guys make the same money? How much money will they both have?

They will make the same amount of money when they sell 48 items, and they will make $2160.

We will let x be the number of items each sells.  Tom's sales are represented by 45x.  Sam's sales are represented by 149x, but we have to take off the amount of his order, so we have 149x-4992.  Setting them equal, we have:

45x = 149x-4992

Subtracting 45x from both sides, we have:
45x-45x = 149x-4992-45x
0 = 104x-4992

Adding 4992 to both sides,
0+4992 = 104x-4992+4992
4992 = 104x

Divide both sides by 104:
4992/104 = 104x/104
48 = x

When they sell 48 items, Tom will make 48(45) = 2160.  This will be the same as Sam's, 149(48)-4992 = 2160.