1 answer
(click or scroll down)
1. Recursive formula: a(n) = a(n-1) + 2
2. Explicit formula: a(n) = 7 + 2(n-1) = 2n + 5
3. Plug in n = 12 into the explicit formula: a(12) = 2(12) + 5 = 24 + 5 = 29 seats in the 12th row.