At the Wild Thing Zoo, you can rent a motorized cart to tour the grounds for a $9 initial charge and $7 per hour. An equation that represents the total cost y for x hours is y = 9 + 7x. At Safari Zoo, you can rent the same cart for a $5 initial charge and $8 per hour. An equation that represents the total cost y for x hours is y = 5 + 8x. For how many hours is the total charge the same? What is the charge for the rental at that time?
How about just solving
5 + 8x = 9 + 7x ?
(can be done in 1.5 seconds in your head.)