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Solve the equation 2x^2+16x-11=-7 by completing the square. Show your work Please.

User Audience
by
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1 Answer

3 votes
  • Answer:

x₁ = - 4 + 3√2

x₂ = - 4 - 3√2

  • Explanation:

Hi !

2x² + 16x - 11 = - 7

2x² + 16x - 11 + 7 = 0

2x² + 16x - 4 = 0 | : 2

x² + 8x - 2 = 0

a = 1 ; b = 8 ; c = - 2

x = (- b ± √b² - 4ac)/2a

x = (-8 ± √8² - 4×1×-2)/2×1

x = 2(-4 ± √3√2)/2

x = - 4 ± 3√2

x₁ = - 4 + 3√2

x₂ = - 4 - 3√2

Good luck !

User StvnBrkdll
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