How many solutions are there to this nonlinear system?

Use mathematical induction to prove the statement is true for all positive integers n, or show why it is false. 1^2 + 4^2 + 7^2 + + (3n - 2)^2 = [n(6n^2-3n-1)/2]

If 5x - 2 = -12, then x = a) -50 b) -4.4 c) -2.8 d) -2

Complete this sentence with the best of choices given