SOLUTION: How do you work the problem x to the second minus x equals 8

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Question 802409: How do you work the problem x to the second minus x equals 8
Answer by homeworkhedgehog(9) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-x=8
This is a quadratic equation. You can tell because 2 is the highest power. If you are solving for x, then you have to get all the terms on one side and an "=0" on the other. So you need to subtract 8 from both sides, resulting in x%5E2-x-8=0. Now there at least two ways to solve this: Factoring, or the Quadratic Equation. This does not factor nicely, so we'll just use the Quadratic Equation x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+.
Quadratic Standard Form Ax%5E2%2BBx%2BC=0 is the form we need to use for this. Looking at the coefficients gives us our A=1, B=-1, and C=-8. We plug these into the equation to get our answer:

x+=+%281+%2B-+sqrt%281%2B32%29%29%2F2
x+=+%281+%2B-+sqrt%2833%29%29%2F2
And that is about as far as we can go without using a calculator to simplify. If you want a decimal answer, you can plug into the calculator %281+%2B+sqrt%2833%29%29%2F2 and %281+-+sqrt%2833%29%29%2F2 to give you x=3.372 and x=-2.372