Assessment Problem:

Is there a value for x that will make (2x – 6)(x – 3) < 0 true?

Mathematical Issues:

Can students reason to an answer without trying to solve the inequality? They must think about zero and negatives in order to accurately address the problem.

Domain:

Algebraic Relations

Theme:

Thinking about Inequalities

Common Core Standards:

6.EE.5

6.EE.8

Encyclopedia Entry:

http://www.algebraicthinking.org/wiki/algebraic-relations-inequalities

Research References:

Lim, K. H. (2006). Characterizing students' thinking: Algebraic inequalities and equations. Paper presented at the 28th annual meeting of the North American Chapter of the International Group for the Psychology of Mathematics Education, Mérida, México: Universidad Pedagógica Nacional.