SOLUTION: Re function f(x)=3x(squared)-x-2 If f(x)=-2, what is x?

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Question 146768: Re function f(x)=3x(squared)-x-2
If f(x)=-2, what is x?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29=3x%5E2-x-2+ Start with the given function


-2=3x%5E2-x-2+ Plug in f%28x%29=-2


0=3x%5E2-x Add 2 to both sides


0=x%283x-1%29 Factor the right side.


x=0 or 3x-1=0 Set each factor equal to zero. Remember, if A%2AB=0 then either A=0 or B=0.


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So our 1st answer is x=0.


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Now let's solve the 2nd equation 3x-1=0


3x-1=0 Start with the given equation.


3x=0%2B1 Add 1 to both sides.


3x=1 Combine like terms on the right side.


x=%281%29%2F%283%29 Divide both sides by 3 to isolate x.




So our 2nd answer is x=1%2F3.


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Answer:


So the solutions are:


x=0 or x=1%2F3