What is the ninth term of the arithmetic sequence defined by the rule a(n)= -14+(n-1)(2)

If you start counting from 0, you ninth term will be 8. Replace n=8 and calculate:
A(8) = -14 + (8-1)(2) = -14 + (7)(2) = -14 + 14 = 0

If you start counting from 1, your ninth term will be 9. Replace n=9 and calculate:
A(9) = -14 + (9-1)(2) = -14 + (8)(2) = -14 + 16 = 2