Graphs of Functions

Every input-output pair ($x$, f($x$)) can be plotted as a point on a coordinate plane, with $x$ along the horizontal axis and f($x$) along the vertical axis. Joining the points shows the shape of the function.

A function of the form f($x$) = mx + c always graphs as a straight line. A function with an $x^2$ term, like f($x$) = $x^2$, graphs as a curve called a parabola.