3x^2 + 7x + 2 = 0, factorisation would look as 3(x + 1\3)(x + 2)
6x^ 2+ 4x - 5=0 => 6(x^2 + 4x/6 - 5/6) => 6(x^2 + 2* 4x/6 * 1/2 - 5/6) => 6(x^2 + 2 * x *1/3 + (1/3)^2 - (1/3)^2 - 5/6) =>
=> 6(x^2 + 2 * x *1/3 + (1/3)^2 - 1/9 - 5/6) => 6(x^2 + 2 * x *1/3 + (1/3)^2 - 17/18) => 6(x^2 + 1/3)^2 - 17/3