Answer: f(x) = -9x
Explanation:
Remember that f(x) is the same thing as y.
y = 3x + 6x + 2y
First, combine like terms to get...
y = 9x + 2y
Then, subtract -2y from each side to get..
-y = 9x
Next, you divide by -1 and get...
y = -9x ,which is your answer
Hope this is helpful :)