RebeckaI LOVE questions like this one. I challenge my Honors kids with these types of problems. I make a big deal of asking for AN equation rather than THE equation for questions like this because I want them thinking about different ways to structure such equations. Even when I know there is one logical answer, I want them thinking about possibilities.
Very good point, Mr. Dardy. Honestly, before I worked through the solution, I thought, "Is there really just one such function?" The struggle is always good...it's just a matter of convincing students of this fact. :)
Tell me what you think!