3x^2+6x-4=0

3x^2+6x-4=0
3x^2+6x-4=0

3x^2+6x-4=0
3x^2+6x-4=0
x^2+2x-4/3=0
x^2+2x+1-1-4/3=0
(x+1)^2-7/3=0
(x+1)^2-21/9=0
(x+1-√21/3)(x+1+√21/3)=0
x=√21/3-1或x=-√21/3-1

3x^2+6x-4=0
3(x^2+2x+1-1)-4=0
3(x-1)^2=7
(x-1)^2=7/3
x-1=正负根号21/3
x=正负根号21/3+1

3(x²+2x-4/3）=0
3（x²+2x+1-1-4/3）=0
3（x+1）²-7=0
3（x+1）²=7
（x+1）²=7/3
x+1=正负根号21/3
x1=(根号21/3)-1 x2=(-根号21/3）-1