How Do I Solve X^2+3x-5=0 By Completing The Square?

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Oddman answered
The constant term in a complete square is the square of half the x coefficient.
  X^2 + 3x - 5 = 0
  x^2 + 3x = 5    (add 5 to both sides)
  x^2 + 3x + (3/2)^2 = 5 + (3/2)^2    (complete the square on the left, add the same amount on the right so the equal sign is still true)
  (x + 1.5)^2 = 5 + 2.25    (show the square, change to decimal for clarity)
  x + 1.5 = ±√7.25    (square root both sides. Note we need ± .)
  x = -1.5 ± √7.25    (subtract 1.5 from both sides)

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