SOLUTION: X^2+5x+6=0

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Question 1030050: X^2+5x+6=0
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
I can complete the square
+x%5E2+%2B+5x+%2B+6+=+0+
+x%5E2+%2B+5x+%2B+%285%2F2%29%5E2+=+-6+%2B+%285%2F2%29%5E2+
+x%5E2+%2B+5x+%2B+25%2F4+=+-24%2F4+%2B+25%2F4+
+x%5E2+%2B+5x+%2B+25%2F4+=+1%2F4+
+%28+x+%2B+5%2F2+%29%5E2+=+%281%2F2%29%5E2+
+x+%2B+5%2F2+=+1%2F2+
+x+=+-5%2F2+%2B+1%2F2+
+x+=+-2+
and, also:
+x+%2B+5%2F2+=+-1%2F2+
+x+=+-5%2F2+-+1%2F2+
+x+=+-3+
----------------------
check:
+%28+x+%2B+2+%29%2A%28+x+%2B+3+%29+=+x%5E2+%2B+5x+%2B+6+
+x%5E2+%2B+5x+%2B+6+=+x%5E2+%2B+5x+%2B+6+
OK
Here's the plot:
+graph%28+400%2C+400%2C+-10%2C+2%2C+-2%2C+10%2C+x%5E2+%2B+5x+%2B+6+%29+