Tìm x biết: -2/5.l 5x - 1/2 l = -4/15 = 1/2

Tìm x biết :
a) -2/5.l 5x - 1/2 l = -4/15 = 1/2
b) 4/3 - 1/2. l x - 3 l = 1/4. l -x + 3 l- 1/3
c) -6/7. l 2x - 1 l + 3/14 = 1/2 - 5/4
d) 1/2. l x + 1/2 l - 3. l x - 3/2 ) = 3/4x
e) 5/2.( x - 3/5 ) - 1/5 = x - 3