Question 135359: Could someone please tell me where I am going wrong? I keep getting -21 and -3 but the answer is (-00, -3) and (10, 00). Thank You.
Solve the inequality:
x+21/x+3 <2
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Solve the inequality:
x+21/x+3 <2
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Solve (x+21)/(x+3) = 2
x+21 = 2x+6
x = 15
Draw a number line; mark x = --3 and x=15 on the line
The inequality is true for x=-21 but undefined for x=-3.
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Test a value in each of the three resulting intervals:
If x=-22 you get (-1/-19)<2 which is true so solutions in (-inf,-3]
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If x= 0 you get (21/3)<7 which is false so no solutions in (-3,15)
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If x = 16 you get (37/19)<2 which is true so solutions in (15,+inf)
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Solution: -inf < x < -3 OR 15 < x < +inf
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Cheers,
Stan H.
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