Yikes, looks like you need to work out that last part... ugh.
(x + 1)(x + 1)
(x + 1)²
2.24489795918
Is the answer
There are 12 possible ways, simply by multiplying the number of sandwiches and drinks you'll find the solution to the problem
Brianna doesn’t have any interest, determined by the 0% APR for 20 months. This is 1 year and 8 months. If she plans on making the payments for 4 years then her interest months is 4 years (48 months) minus 20 months, leaving her with 28 months of being charged interest. 28 months is 2 years and 4 months.