If f(x) = x2 -7x + a and f(a) = -9 then compute f(12)

Answer 1

f(x) = x² - 7x + a

For f(a) = -9

-9 = a² - 7a + a

-9 = a² - 6a

0 = a² - 6a + 9

0 = (a-3)²

a = 3

f(x) = x² - 7x + 3

f(12) = ____?

Plug in x = 12 and compute the answer.