What is the axis of symmetry of the function f (x) = - (x+9) (x-21)

Question

Mathematics

Ryland

24 May, 20:25

What is the axis of symmetry of the function f (x) = - (x+9) (x-21)

+3

Answers (1)

Know the Answer?

Brandon Santana · Answer 1

f (x) = - (x+9) (x-21)

Manipulating algebrically,

We get,

f (x) = - (x+9) (x-21)

= - (x^2 - 21x + 9x - 189)

= - (x^2 - 12x - 189)

= - x^2 + 12x + 189

Axis of symmetry = - b/2a

plugging the values,

x = - 12/-2

= 6