This handout describes interval notation and helps students make the leap from a number line to domain and range. Students must have prior knowledge of the definitions of domain and range and should be comfortable with "all real numbers such that..." notation.
Students start by writing interval notation for graphed number lines. They then make the connection that the x-and y- axes are nothing more than horizontal and vertical number lines.
An interactive box with 36 graphs are also included to let students practice writing interval notation. Students can use the flaps of the box to help identify the domain and range. Cards 1 - 22 are graphs often encountered in an Algebra II class. Cards 23 - 36 are encountered in Pre-Calculus.