SOLUTION: what are the solutions to the equation x^2+7x=-12

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Question 427167: what are the solutions to the equation x^2+7x=-12
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B7x=-12
To complete the square, take 1/2 of the
coefficient of x, square it, and add
it to both sides
+x%5E2+%2B+7x+%2B+%287%2F2%29%5E2+=+-12+%2B+%287%2F2%29%5E2+
+x%5E2+%2B+7x+%2B+49%2F4+=+-48%2F4+%2B+49%2F4+
+%28+x+%2B+7%2F2+%29%5E2+=+1%2F4+
take the square root of both side
+x+%2B+7%2F2+=+1%2F2+
+x+=+-3+
and
+x+%2B+7%2F2+=+-1%2F2+
+x+=+-4+
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You can check by plugging in -3 for x
and then -4 for x