# How do you write f(x) = x^2 + 14x +45 in vertex form?

Jul 29, 2017

$f \left(x\right) = {\left(x + 7\right)}^{2} - 4$

#### Explanation:

x-coordinate of vertex:
$x = - \frac{b}{2 a} = - \frac{14}{2} = - 7$
y-coordinate of vertex:
$f \left(- 7\right) = 49 - 98 + 45 = - 4$
Vertex form of f(x) :
$f \left(x\right) = {\left(x + 7\right)}^{2} - 4$