SOLUTION: For what real number k does 3x2  k factor as 3(x  2)(x + 2)?

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Question 194722: For what real number k does 3x2  k factor as
3(x  2)(x + 2)?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Since we want 3x%5E2-k to factor to 3%28x-2%29%28x%2B2%29, this means that we want 3x%5E2-k=3%28x-2%29%28x%2B2%29


3x%5E2-k=3%28x-2%29%28x%2B2%29 Start with the given equation.


3x%5E2-k=3%28x%5E2%2B2x-2x-4%29 FOIL


3x%5E2-k=3%28x%5E2-4%29 Combine like terms.


3x%5E2-k=3x%5E2-12 Distribute


-k=-12 Subtract 3x%5E2 from both sides.


k=12 Divide both sides by -1 to isolate "k".


So the solution is k=12 which means that 3x%5E2-12 factors to 3%28x-2%29%28x%2B2%29