Tìm x, biết: a) 5x^3 - 20x = 0; b) x^2 - 8x = -16; c) (x - 1)^2 + x(5 - x) = 0

Tìm x, biết:
a) 5x^3-20x=0
b) x^2-8x=-16
c) (x-1)^2+x(5-x) =0
d) x^2-3x=0
e) x(2x-7)-4x+14=0
f) (x-2)(2x-3)-x(2x+1)=2
g) 2x(4x-1)+12x-3=0
h) 3x^2-3x(2+x) =36
i) x(x+3)-5(x+3)=0