Sarah runs a day camp in the summer and needs to buy paper towels and soap for the restrooms. she spends $129 on t cases of paper towels and s cases of soap. each case of paper towels is $12 and contains 10 rolls of paper towels. each case of soap $15 and contains 12 bottles of soap. sarah buy 10 cases of supplies all together a. write a system of two equations to represent the cases of supplies sarah buys. explain your work