# How do I use the vertex formula to determine the vertex of the graph for #f(x) = −x^2 + 18x − 75#?

##### 2 Answers

May 1, 2015

The vertex formula has the form

with a vertex at

Converting

into the vertex formula form is a matter of "completing the square"

The vertex is at

May 1, 2015

The vertex formula says that the graph of

In this equation, we have

The formula tells us that the

To find the

The vertex is