(3x +1)^2 - (3x - 1)^2 = 11x + 1.2
9x^2 + 6x + 1 - (9x^2 - 6x + 1) = 11x +1.2
9x^2 + 6x + 1 - 9x^2 + 6x - 1 = 11x +1.2
12x - 11x = 1.2
x = 1.2
(3х+1)²-(3х-1)²=11х+1,2
(3x+1-(3x-1))(3x+1+3x-1)=11х+1,2
(3x+1-3x+1)6x=11х+1,2
2*6x=11х+1,2
12x=11х+1,2
x=1,2
(3x +1)^2 - (3x - 1)^2 = 11x + 1.2
9x^2 + 6x + 1 - (9x^2 - 6x + 1) = 11x +1.2
9x^2 + 6x + 1 - 9x^2 + 6x - 1 = 11x +1.2
12x - 11x = 1.2
x = 1.2
(3х+1)²-(3х-1)²=11х+1,2
(3x+1-(3x-1))(3x+1+3x-1)=11х+1,2
(3x+1-3x+1)6x=11х+1,2
2*6x=11х+1,2
12x=11х+1,2
x=1,2