You can put this solution on YOUR website! x2+12x-3 what value should be on each side to complete the square?
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x^2+12x-3 = y
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x^2+12x + ? = y + 3 + ?
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Complete the square:
x^2 + 12x + 6^2 = y + 3 + 6^2
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Factor:
(x+6)^2 = y + 39
etc.
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Answer to your question: 6^2 or 36
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Cheers,
Stan H.