Replacing

I have had many people say to me over the years, "But algebra is easy: just tell them to do the same thing to both sides!" This is wrong in several ways, not least of which is the word "easy". The particular way it's wrong that I want to talk about today is the idea that doing the same thing to both sides is somehow the only move in algebra, because it's not even the most important or the most common move.

You can read the rest of this blog post, and the other posts in the series across the years, in PDF form here.

The titles of the five blog posts are:

• The reorder of operations
• (Holding it together)
• The Operation Tower
• Replacing
• Sticky operations