SOLUTION: x(squared)-4x=-3 Solve for x PLEASE

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Question 609378: x(squared)-4x=-3 Solve for x PLEASE
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2+-+4x+=+-3+
You can complete the square
Take 1/2 of the coefficient of x,
square it, and add it to both sides
+x%5E2+-+4x+%2B+%28-4%2F2%29%5E2+=+-3+%2B+%28-4%2F2%29%5E2+
+x%5E2+-+4x+%2B+4+=+-3+%2B+4+
+%28+x+-+2+%29%5E2+=+1+
Take the square root of both sides
+x-2+=+1+
+x+=+3+
and, also
+x-2+=+-1+
+x+=+1+
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Check by plugging the answers back into equation
+x%5E2+-+4x+=+-3+
+3%5E2+-+4%2A3+=+-3+
+9+-+12+=+-3+
+-3+=+-3+
and
+x%5E2+-+4x+=+-3+
+1%5E2+-+4%2A1+=+-3+
+1+-4+=+-3+
+-3+=+-3+
OK