SOLUTION: whats the answer to x2=8x+2 using the quadratic formula

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Question 611369: whats the answer to x2=8x+2 using the quadratic formula
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2=8x%2B2
Whether you use the Quadratic formula or factoring, you want one side of the quadratic equation to be a zero. Subtracting 8x and 2 from each side we get:
x%5E2-8x-2=0
Now we can use the quadratic formula:
x+=+%28-%28-8%29+%2B-+sqrt%28%28-8%29%5E2+-+4%281%29%28-2%29%29%29%2F2%281%29
Simplifying:
x+=+%28-%28-8%29+%2B-+sqrt%2864+-+4%281%29%28-2%29%29%29%2F2%281%29
x+=+%28-%28-8%29+%2B-+sqrt%2864+%2B+8%29%29%2F2%281%29
x+=+%28-%28-8%29+%2B-+sqrt%2872%29%29%2F2%281%29
x+=+%288+%2B-+sqrt%2872%29%29%2F2
x+=+%288+%2B-+sqrt%2836%2A2%29%29%2F2
x+=+%288+%2B-+sqrt%2836%29%2Asqrt%282%29%29%2F2
x+=+%288+%2B-+6%2Asqrt%282%29%29%2F2
x+=+%282%284+%2B-+3%2Asqrt%282%29%29%29%2F2
x+=+%28cross%282%29%284+%2B-+3%2Asqrt%282%29%29%29%2Fcross%282%29
x+=+4+%2B-+3%2Asqrt%282%29
So the solutions to your equation are:
x+=+4+%2B+3%2Asqrt%282%29 or x+=+4+-+3%2Asqrt%282%29