Question 1114174
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If f(x) = 9 - 3x  and  f(x) = 12,   it means


9 - 3x = 12,


9 - 12 = 3x


-3 = 3x  ====>  x = {{{(-3)/3}}} = -1.


<U>Answer</U>.  x = -1.
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