SOLUTION: solve the inequiality x^2+13x+40<5

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Question 554180: solve the inequiality x^2+13x+40<5
Found 2 solutions by stanbon, kkasko:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve the inequality x squared +13 x+40 < 5
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x^2 + 13x + 35 < 0
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x = -3.8074 or x = -9.1926
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Plot those x-values on a number line:
Since the parabola opens up the solution set
must be between the roots:
x^2 + 13x + 35 < 0
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Solutions: -9.1926 < x < -3.8074
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Cheers,
Stan H.
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Answer by kkasko(46) About Me  (Show Source):
You can put this solution on YOUR website!
x^2+13x+40<5
-5-5
x^2+13x+40-5<0
x^2+13x+35<0
put the equation into the quadratic formula
x+=+%28-13%29+%2B-+sqrt%28+13%5E2-4%2A1%2A35+%29%29%2F%282%2A1%29+
x+=+%28-13%29+%2B-+sqrt%2829%29%29%2F%282%29
The discriminant=29 which means there are two solutions since it is greater than zero.
x1=-13+sqrt29/(2)
x1=-3.80741759643275
x2=-13-sqrt29/(2)
x2=-9.19258240356725
-9.19258240356725 < x < -3.80741759643275


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