The equation to represent the number of weeks Lewis needs to work in order to purchase the rings is as follows, y=20x+80. y is the cost of the ring, 20 is how much he gets, x, weeks. 80 is the initial value, the money he already has. Using the equation we can plug y with 260, 260=20x+80. To solve this equation you subtract 80 from each side, 260-80=20x+80-80 which simplified is 180=20x. Then you divide 20 into each side to isolate the variable. 180/20=20x/20 which simplified is 9=x. The answer is, "It will take 9 weeks for Lewis to purchase the ring."
