National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Parabola
Dr. Math, in a reply to a student's question, explains how to find the location of the vertex and focus, calculate the distance between the focus and vertex, as well as identify the axis of symmetry and the directix.
Varsity Tutors
Varsity Tutors: Hotmath: Algebra Review: Axis of Symmetry of a Parabola
Find a quick, concise explanation of the Axis of Symmetry of a Parabola. An example is given to help you understand how to find the axis of symmetry of a parabola.
Math Words
Math words.com: Axis of Symmetry of a Parabola
A basic definition for what the axis of symmetry of a parabola is, along with an illustration.