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Question 253358: x2-4x-5<0
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! x^2-4x-5<0
Factor:
(x-5)(x+1) < 0
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x cannot be 5; x cannot be -1
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Draw a number line and plot x = -1 and x = 5
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Note: The number line is broken into 3 intervals.
Test a check point from each interval in the inequality to determine where the solutions are.
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Test x = -2; you get (-)(-) < 0 ; that is false
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Test x = 4 ; you get (-)(+) < 0 ; true so solutions in (-1,5)
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Test x = 6 ; you get (+)(+)<0 ; that is false
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Ans: All x in (-1,5)
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Cheers,
Stan H.
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