Use the process of completing the square and/or factoring to find the zeros and axis of symmetry for the graph of the function.

f(x) = x^2 - 14x - 72

a.

zeros: x = -4 and x = 18;

axis of symmetry: x = 7

b.

zeros: x = -18 and x = 4;

axis of symmetry: x = -7

c.

zeros: x = -9 and x = -8;

axis of symmetry: x = -7

d.

zeros: x = 9 and x = 8;

axis of symmetry: x = 7

edit: the answer is here.

the axis of symmetry is 7.
the roots were 18 & -4

A)

zeros: x = -4 and x = 18;

axis of symmetry: x = 7

Step-by-step explanation:

Given the equation of function

f(x) = x² - 14x - 72

here a = 2

        b = -14

        c = -72

by using quadratic equation

x1   = 14 + √14² + 4(1)(72) / 2

       = 18

and

x2 = 14 - √14² + 4(1)(72) / 2

     = - 4

It is a vertical line with the equation of  x = -b/2a

                                                                    x = -(-14)/2(1)

                                                                    x = 7