SOLUTION: use the quadratic formula to find any x-intercepts ont he graph of the equation y=3x^2+9x-1

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Question 764801: use the quadratic formula to find any x-intercepts ont he graph of the equation
y=3x^2+9x-1

Found 2 solutions by reviewermath, stanbon:
Answer by reviewermath(1029) About Me  (Show Source):
You can put this solution on YOUR website!
Q: use the quadratic formula to find any x-intercepts on the graph of the equation
y=3x^2+9x-1
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A:
Quadratic Formula:x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
In 3x%5E2%2B9x-1+=+0, a = 3, b = 9, and c = -1
Using quadratic formula
x+=+%28-9+%2B-+sqrt%28+9%5E2-4%2A3%2A%28-1%29+%29%29%2F%282%2A3%29+
x+=+%28-9+%2B-+sqrt%28+93+%29%29%2F%286%29+
The x-intercepts are (%28-9+%2B+sqrt%28+93+%29%29%2F%286%29+, 0) and (%28-9+-+sqrt%28+93+%29%29%2F%286%29+, 0).

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
y=3x^2+9x-1
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x = [-9 +- sqrt(81-4*3*-1)]/6
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x = [-9 +- sqrt(93)]/6
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x = [-9 +- 9.64]/6
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x = 0.1073 or x = -3.1067
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Cheers,
Stan H.
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