1.{(x-4)/2}-{(2x+5)/5}=-1 2.2x-½=3/2 3.x/5-2=½(x-1)

1.
[tex] \frac{x-4}{2}- \frac{2x+5}{5} = -1\\ \frac{5(x-4) - 2(2x+5)}{10} = -1\\ 5x - 20 - 4x - 10 = - 10\\ x -30 = -10\\ x = -10 + 30 = 20 [/tex]

2.
[tex]2x - \frac{1}{2} = \frac{3}{2}\\ 2x = \frac{3}{2} + \frac{1}{2}\\ 2x = 4 \\\\ x = \frac{4}{2} = 2 [/tex]

3.
[tex] \frac{x}{5}-2 = \frac{1}{2}(x-1) [/tex]
---------------------------------------------- x 10
     2x - 20  = 5x - 5
     5x - 2x  = -20 + 5
         3x     = -15
            x    = [tex] \frac{-15}{3} [/tex] 
                  = -5