Undoing the steps/backtracking

I’ve seen this approach in both CME and also in the Discovering Algebra series. I like it as a concrete model for introducing solving equations. It also meshes well with using number tricks to approach algebraic expressions (which both of these curricula do as well).

Here are some resources for introducing solving equations via backtracking/undoing the steps:

Reminder: Things get awkward when you try to backtrack from expressions such as 5 - x. For these, there’s no getting around observing that 5-x = 5 + (-x) = -x + 5, but that needs to be done explicitly.

Advertisements

2 thoughts on “Undoing the steps/backtracking

  1. Pingback: NumberTricks for expressions | Algebra One Blog

  2. Pingback: Algorithms for finding inverses | Algebra 2 Blog

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s