Which model do you think is best to show division?

At a sale this week, a desk is being sold for $213. this is a 29% discount from the original price. what is the original price?

Your food costs are $5,500. your total food sales are $11,000. what percent of your food sales do the food costs represent?

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?