1) (y+4) / (y+2) - (2y-1) / y = 0
[y(y+4) - (2y-1)(y+2)] / [y(y+2)] = 0
y ≠ 0; y ≠ - 2
y^2 + 4y - 2y^2 - 3y + 2 = 0
-y^2 + y + 2 = - (y+1)(y-2) = 0
y1 = - 1; y2 = 2
2) (3x^2 - 5x - 2) / (2 - x) = 0
x ≠ 2
3x^2 - 5x - 2 = (x-2)(3x+1) = 0
x = - 1/3; x ≠ 2
3) (3x^2 + 11x - 4) / (3x - 1) - 3 = 0
(3x^2 + 11x - 4 - 3(3x-1)) / (3x-1) = 0
x ≠ 1/3
3x^2 + 11x - 4 - 9x + 3 = 0
3x^2 + 2x - 1 = (x+1)(3x-1) = 0
x = - 1; x ≠ 1/3