Assessment Problem:

1. Solve the equation 2(3x+4) = 6x + 9

2. After solving, could you solve it in another way?

3. What would be the relationship between the graphs of each side of the equation?

Common Responses:

The correct answer is empty set, meaning that there is no answer. This equation is a false equation (meaning that it leads to a contradiction).

Graphically each side of the equation represents a line and these lines are parallel to each other. 59% of high school student-pairs answered this question correctly. 57% of the participants used symbolic manipulation as their first choice of strategy.

Domain:

Algebraic Relations

Theme:

Solving equations

Common Core Standards:

6.EE Expressions and Equations

Research References:

(Huntley, Marcus, Kahan, & Miller, 2007)