4. At Ice Skating Palace skates and safety equipment cost $3.50 per hour. If you have your own shoes, the safety equipment is $1.50 per hour. Your friend is selling used skates for $40, or you can rent some. Either way, you must rent safety equipment. a. Write an equation for the total cost if you rent skates. Use h to represent the hours.

a. Write an equation for the total cost if you buy used skates and use your own. Let h represent the number of hours.