Tìm x, 9x^2 - 6x - 3 = 0, x^3 + 9x^2 + 27x + 19 = 0, 4x^2 - 12x - 12x + 9 = 0, x^2 - 6x + 10 = 0

Tìm x
a, 9x^2-6x-3=0
b, x^3+9x^2+27x+19=0
c, 4x^2-12x-12x+9=0
d, x^2-6x+10=0