Advanced Algebra: Example 2

We are looking for the choice that will result in when 2 is plugged in for S:

Choice (A): . Eliminate.
Choice (B): . Eliminate.
Choice (C): . Eliminate.
Choice (D): . Correct.
Choice (E): . Eliminate.

By using the Picking Numbers strategy, we were able to find the answer quickly. The algebraic approach is a little tricky to identify, requires calculation with variables, and contains a subtle last step. On an algebra problem that doesn't have a familiar structure (unlike, for example, a quadratic) and that has multiple variables, consider Picking Numbers. It may save you some time and decrease your chances for error.