The PDF linked below challenges students to demonstrate an understanding of equations and inequalities. They must be able to understand the meaning of equivalent forms of expressions, equations, inequalities, or relations. A student must make sense of given equations and inequalities and determine specific values that make the statement true. A student must understand and be able to determine which equations and inequalities have just two solutions, which ones have more than two solutions, which ones have infinite solutions, and which ones have fewer than infinite but more than two solutions. A student must be able to justify their reasoning.

http://www.insidemathematics.org/common-core-math-tasks/high-school/HS-A-2007%20Two%20Solutions.pdf