Vertex Form

Quadratic Functions can be written in three different forms. The last lesson discussed the standard form of a quadratic. This lesson will discuss vertex form of a quadratic. The vertex form of a quadratic equation is:

y = a(x-h)² + k

Properties of Graphs in Vertex Form:

• When a is positive the graph opens upward; when a is negative the graph opens downward
• When h is positive the graph shifts right; when h is negative the graph shifts left.
• When k is positive the graph shifts up; when k is negative the graph shifts down.
• The vertex is the point ( h, k ) and the axis of symmetry is the line x = h .