SOLUTION: solve the following by completing the square 7x(squared)-7x-1=0

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Question 834332: solve the following by completing the square
7x(squared)-7x-1=0
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+7x%5E2+-+7x+-++1+=+0+
+7x%5E2+-+7x+=+1+
+x%5E2+-+x+=+1%2F7+
+x%5E2+-+x+%2B+%28-1%2F2%29%5E2+=+1%2F7+%2B+%28-1%2F2%29%5E2+
+x%5E2+-+x+%2B+1%2F4+=+1%2F7+%2B+1%2F4+
+x%5E2+-+x+%2B+1%2F4+=+4%2F28+%2B+7%2F28+
+%28+x+-+1%2F2+%29%5E2+=+11%2F28+
+x+-+1%2F2+=+sqrt%28+11%2F28+%29+
+x+=+1%2F2+%2B+sqrt%28+11%2F28+%29+
and
+x+=+1%2F2+-+sqrt%28+11%2F28+%29+
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Just to make it a lot easier, I'll check
by converting to decimals
+x+=+.5+%2B+.62678+
+x+=+1.12678+
+7x%5E2+-+7x+-++1+=+0+
+7%28+1.12678+%29%5E2+-+7%2A1.12678+-++1+=+0+
+8.8874+-+7.8875+-+1+=+0+
+-.0001+=+0+
error due to rounding off -OK