SOLUTION: Completing the square x^2-4x=5

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Question 750568: Completing the square x^2-4x=5
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2+-+4x+=+5+
+x%5E2+-+4x+%2B+%28-4%2F2%29%5E2+=+5+%2B+%28-4%2F2%29%5E2+
+x%5E2+-+4x+%2B+4+=+5+%2B+4+
+x%5E2+-+4x+%2B+4+=+9+
+%28+x+-+2+%29%5E2+=+3%5E2+
+x+-+2+=+3+
+x+=+5+
and, also,
+x+-+2+=+-3+
+x+=+-1+
------------
check:
+%28+x+-+5+%29%2A%28+x+%2B+1+%29+=+x%5E2+-+4x+-+5+
+x%5E2+-+4x+=+5+
OK