Tìm x, biết: a) |x.(x - 5)| = |x|; b) |x^2 - 9| = 2.|x - 3|; c) |3x^2 - 6x| = |x - 2|; d) |7x - 14x^2| - |1 - 2x| = 0

Tìm x, biết
a) |x.(x-5)|=|x|
b) |x^2-9|=2.|x-3|
c) |3x^2-6x|=|x-2|
d) |7x-14x^2|-|1-2x|=0
e) |3x^2+6x|+6.|x|=0
f) |4-25x^2|-|2+5x|=0