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Expert: Steve Holleran - 10/25/2007


Question
I'm having trouble finding the x-intercept for this problem.

3x^2-12x-1

Answer
Hi Ryan,

Okay, the x-intercept is where y = 0, so we have

            3x^2 - 12x - 1 = 0

using the quadratic formula, you have

   x = [12 +/- sqrt(144 -4(3*-1))] / 6

     = [12 +/- sqrt(156)] / 6

    = 2 +/- sqrt(156) / 6  = 4.08 or -0.08

Hope this helps.
Steve

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Steve Holleran

Expertise

I can help with all math questions from basic math to Calculus. Whether it`s consumer questions, or questions from high school or college students, I have probably dealt with it at some time in my career.

Experience

33 years teaching experience in NJ public schools

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B.S. Mathematics : Wake Forest University 1972 M.S. Mathematics : Monmouth University 1981

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