Brianna wants to buy a digital camera for a photography class. One store offers the camera for $51 down and a payment plan of $21 per month. The payment plan for a second store is described by y = 15x + 80, where y is the total cost in dollars and x is the number of months. Which camera is cheaper when the camera is paid off in 12 months? Complete the explanation.

The camera at the
(select)
store is cheaper when the camera is paid off in 12 months, because the cost at the first store is $
and the cost at the second store is $
.