Well now you've got me trying to figure out what the three or four things are! LOL... If you count "factoring" as one thing (although it covers several chapters when you go into the detail of linear vs. quadratic and simple quadratic vs. completing the square and/or the quadratic equation), that's a start... then maybe "isolating a variable" could include all the rules of manipulating equations and situations where one equation will do vs. when you need two or three...

Hey, that covers most of it right there! Maybe there are only two things you need... wink

Erica