SOLUTION: Solve the equation by completing the square: x^2 + 8x = 14 can someone help me please with this problem? i am having a really hard time trying to figure this out.

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Question 601411: Solve the equation by completing the square: x^2 + 8x = 14
can someone help me please with this problem? i am having a really hard time trying to figure this out.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
To complete the square, take 1/2 of the
coefficient of the +x+ term, square it,
and add it to both sides.
+x%5E2+%2B+8x+=+14+
+x%5E2+%2B+8x+%2B+%288%2F2%29%5E2+=+14+%2B+%288%2F2%29%5E2+
+x%5E2+%2B+8x+%2B+16+=+14+%2B+16+
+%28+x+%2B+4+%29%5E2+=+30+
Take the square root of both sides
+x+%2B+4+=+sqrt%2830%29+
+x+=+-4+%2B+sqrt%2830%29+
and also, taking the negative square root,
+x+=+-4+-+sqrt%2830%29+
------------------
check the answers:
+%28+-4+-+sqrt%2830%29+%29%5E2+%2B+8%2A%28++-4+-++sqrt%2830%29%29+=+14+
+16+%2B+8%2Asqrt%2830%29+%2B+30+-+32+-+8%2Asqrt%2830%29+=+14+
+16+%2B+30+-+32+=+14+
+14+=+14+
OK- you can check the other answer