1) 3x^2 - 2x -4 = 0; 2) (x - 3)^4 - 4(x - 3)^2 - 21 = 0

$1) 3 x^{2} - 2 x - 4 = 0 2) {(x - 3)}^{4} - 4 {(x - 3)}^{2} - 21 = 0$