Question

What is the only solution of 2x2 + 8x = x2 – 16?

Answer 1

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Equation Given
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`2x^2 + 8x = x^2 -16`

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Subtract x² + 16 from both sides
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`2x^2 -x^2 + 8x + 16 = 0`

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Combine like terms
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`x^2 + 8x + 16 = 0`

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Factorize
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`(x + 4)^2 = 0`

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Square root both sides
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`x + 4 = 0`

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Take away 4 from both sides
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`x = - 4`

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Answer: x = - 4
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