Nancy flew home from vacation with a heavy bag. With the first airline she flew, Nancy had to pay $20 to check her bag, plus $5 for every pound that her bag was over the weight limit. The next flight was with another airline that had the same weight limit. Nancy had to pay $4 per pound that her bag was over the weight limit, in addition to the checked bag fee of $25. By coincidence, the fees ended up being the same with both airlines. How far over the weight limit was the bag? Write a system of equations, graph them, and type the solution.​