Tag Archives: Cartesian coordinate system

Origins of the Coordinate Plane

One of the legends of math relates to the invention of the coordinate plane system. The legend states that Descartes was inspired to invent this system after watching a fly move around on the ceiling over his bed. This post tells the story and points out its relevance for modern math teachers.

Not all variables are created equal

Variables do not all serve the same purpose. Making this clear helps students more deeply understand algebraic equations, such as the equation for a line. This post shows how to understand the two kinds of variables in the slope-intercept form of a linear equation.