real or imaginary solutions

Question

Find the real or imaginary solutions by completing the square. 2x^2+5x-1=0 

I need help with this question for algebra class. thank you in advance!

Answer 1

2x^2+5x-1=0

2x^2+5x=1

x^2+(5/2)x=1/2

(1/2)(5/2)=5/4

(5/4)^2=25/16

x^2+(5/2)x+(25/16)=(1/2)+(25/16)

(x+[5/4])^2=(8/16)+(25/16)

(x+[5/4])^2=(33/16)

take the square root of both sides

x+[5/4]=±√(33/16)

x+[5/4]=±√(33)/4

x=-(5/4)±√(33)/4

x=(-5+√33)/4

x=(-5-√33)/4

Answer 2

The formula to resolution of a general equation  of second grade is:                                      _____

                                                                                                                           - 5  +  V   33

                                                                 _________________              x, =    _____________    =     0.186140661 

                                                     -b  +   V  b^2 - 4  a  c                                             4

                                     x,"  =      ____-______________________                                    _____

                                                                2 a                                                       - 5   -  V   33

                                                              ___________________               x" =  ______________  =    - 2.686140661

                                          -5      +      V  25   - 4 (2) (-1)                                             4

Replacing              x,   =    _______-_________________________

                                                                  4

                                                                  

      When I sent the request the signs moved, I don't no why the first request is positive and the second is negative. sorry for the mistake.