Today there was a great question on social media:
I realized I don’t actually understand what is really happening when you distribute something like 2x(x+5). The 2nd part makes sense because if you have 5 groups of 2 x’s, that makes 10x. Tips on how to articulate how to understand 2x multiplied by x?
I believe the key is visually representing this in addition to questioning so the students develop a conceptual understanding. Here is a video with a short explanation of how I introduce this.
How do you introduce this? I would love to see other ideas!