The first four terms in a sequence are: -1, -4, -7, -10. Write an expression for the nth term of the sequence.

Answer: -3n + 2Explanation: 'n' stands for term number. The 'nth' term is a formula with 'n' in it which enables you to find any term of a sequence. This sequence of numbers changes by the same amount each time (-3), so it must be a constant difference equation. These can be found by doing the equation dn + (a - d) where d is the difference between the terms, a is the first term and n is the term number. For this sequence, d = -3, a = -1, so -3n + ((-1) - (-3)), or -3n + 2.