tolong di kerjakan no.9!

(fog)(x) = (2x-6)² - 4
- 4 = 4x² - 24x + 36 - 4
0 = 4x² - 24x + 36
---------------------------- :4
0 = x² - 6x + 9
0 = (x-3)²
maka
x = 3

jawaban C