Question 15519
Given:  x + y  =-1   ----(1)
        1/x+1/y=1/2 -----(2)  
1/x+1/y=1/2  ===>   (x+y)/xy =1/2
                      x+y = xy/2   (x+y=-1  according to Equation 1)
                      -1 = xy/2  (Substituting x+y with -1 )
                       xy= -2  
  We know that (x-y)^2 = (x+y)^2-4xy
                       = (-1)^2 -4(-2)
                       =  1 -(-8)=1+8=9
               (x-y)^2 = 9
             therefore x - y = 3  ------(3)
                       x + y = -1 ------(1)
adding (3)&(1) we get  2x = 2
                        x = 1

                     x + y = -1
                     1 + y = -1
                         y = -1 -1 = -2
therefore x=1 , y= -2