Question

If r◼s = 3r + s, find 4◼(2◼1).

Answer 1

By definition of ◼, we have

2 ◼ 1 = 3•2 + 1 = 7

4 ◼ (2 ◼ 1) = 4 ◼ 7 = 3•4 + 7 = 19