Write in vertex form and identify h and k and is the vertex minimum or maximum

Question

X^2-6x-16

Write in vertex form and identify h and k and is the vertex minimum or maximum

Answer 1

The vertex form is          a(x - h)² + k

 

where:

a is the coefficient of x² . 

(h, k) is the vertex.  When a is negative, vertex is maximum.  Otherwise, it is a minimum.

 

x² - 6x - 16 = (x² - 6x + 9) - 25

 

                 = (x - 3)(x - 3) - 25

 

                 = (x - 3)² - 25

 

 

From this vertex form, can identity h and k?