SOLUTION: f(x)=x^(2)-6x-2 how to solve

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Question 462630: f(x)=x^(2)-6x-2 how to solve
Answer by math-vortex(648) About Me  (Show Source):
You can put this solution on YOUR website!
Solve f(x)=x^(2)-6x-2
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When you say, "solve," I'm thinking that you want to know the values of x where f(x)=0.
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Let f(x) = 0. Then we have
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x^2 - 6x - 2 = 0
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This is a quadratic equation, so we have two solution methods available: we can use the factoring method, or we can apply the quadratic formula. I don't see an obvious way to factor the left-hand side, so we'll use the quadratic formula.
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The equation is already in the general (standard) form,
ax^2 + bx + c = 0
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We have
a = 1
b = -6
c = -2
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Now, we apply the quadratic formula,
x+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
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We substitute the values for a, b, and c from our quadratic equation into the formula.
x+=+%28-%28-6%29%2B-sqrt%28%28-6%29%5E2-4%281%29%28-2%29%29%29%2F%282%281%29%29
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Now we simplify,
x+=+%286%2B-sqrt%2836%2B8%29%29%2F2
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x+=+%286%2B-sqrt%2844%29%29%2F2
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x+=+%286%2B-2%2A%28sqrt%2811%29%29%29%2F2
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x+=+3%2B-sqrt%2811%29
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The "plus or minus" in the formula give us two roots; either
x+=+3%2Bsqrt%2811%29
or
x+=+3-sqrt%2811%29
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Here is a graph of your equation:
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graph%28+450%2C+300%2C+-5%2C+12%2C+-12%2C+5%2C+x%5E2-6x-2+%29
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hope this helps! If you have questions, feel free to email me at math.in.the.vortex@gmail.com
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Ms.Figgy
math.in.the.vortex