Questions on Algebra: Quadratic Equation answered by real tutors!

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Question 155267: solve by completing the square
2x^2+5x-1=0
the solutions are x=???????????

HELP ME!!! PLEASE: solve by completing the square
2x^2+5x-1=0
the solutions are x=???????????

HELP ME!!! PLEASE
Answer by Earlsdon(3716) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by completing the square:
2x^2+5x-1 = 0 First, divide through by 2 to get the coefficient of x^2 equal to 1.
x^2+(5/2)x-1/2 = 0 Now add 1/2 to both sides.
x^2+(5/2)x = 1/2 Complete the square in the x-terms by add the square of half the x-coefficient (((1/2)(5/2))^2 = highlight(25/16)) to both sides of the equation.
x^2+(5/2)x+highlight(25/16) = 1/2 + highlight(25/16) Simplify, where possible.
x^2+(5/2)x + 25/16 = 33/16 Now factor the left side.
(x+5/4)(x+5/4) = 33/16 Simplify.
(x+5/4)^2 = 33/16 Take the square root of both sides.
(x+5/4) = sqrt(33/16) Simplify.
(x+5/4) = 0+-sqrt(33)/4 Now subtract 5/4 from both sides.
x = (5/4)+-sqrt(33)/4
x = (5+sqrt(33))/4 or x = (5-sqrt(33))/4