The

vertex of a parabola is the high

point or low

point of the graph. The method you use to find the

vertex will depend on the form in which the

function is given.

You will want to use one strategy when the

function is given in

vertex form

. The reason this is called the

vertex form is because the

vertex is at the

point (h, k). Notice that the value of h is the opposite of what it is in the function, but the value of k has the same sign. So when a

function is already presented in this form, the

vertex is found simply by looking at the numbers in the function.

You will want to use a different strategy when the

function is given in standard form

. You can either use a formula or manipulate the

function into

vertex form. All strategies will be shown in the examples below.