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Solve -4x^2+5x+17=0 by completing the square

User DonSaada
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Final answer:

To solve the quadratic equation -4x^2+5x+17=0 by completing the square, divide all terms by -4, then complete the square on the left side by adding the square of half of the x coefficient to both sides. Finally, write the left side as a perfect square and solve for x.

Step-by-step explanation:

To solve the quadratic equation -4x^2+5x+17=0 by completing the square, follow these steps:

  1. Move the constant term to the right side of the equation: -4x^2 + 5x = -17.
  2. Divide all terms by the coefficient of x^2, which is -4: x^2 - (5/4)x = 17/4.
  3. To complete the square, add the square of half the coefficient of x to both sides of the equation. In this case, add ((5/8)^2) to get x^2 - (5/4)x + (25/64) = 17/4 + (25/64).
  4. Write the left side as a perfect square: (x - (5/8))^2 = 17/4 + (25/64).
  5. Simplify the right side and solve for x by taking the square root of both sides, remembering to consider both the positive and negative square roots.

By completing these steps, you will find the solutions to the original equation.

User Norman Maurer
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