Question

Consider the quadratic function:

Answer 1

Answer:

Step-by-step explanation:

hello :

f(x) = x² – 8x – 9 = (x²-8x+16)-16-9  

f(x) = (x-4)²-25  ..... vertex form

the vertex is : (4 ; -25)

Answer 2

$f(x) = x^2 - 8x -9\\\\x_0=\frac{8}{2} =4\\\\y_0=4^2-8*4-9=-25$

Vertex: (4;-25)

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