x^2+4x=2
(x+2)^2=6
x+2=√6或x+2=-√6
x=√6-2或x=-√6 -2
5x^2-4x-12=0
(5x+6)(x-2)=0
x=-6/5或x=2
4x^2+4x+10=1-8x
4x^2+12x+9=0
(2x+3)^2=0
2x+3=0
x=-3/2
x^2-6x+1=0
(x-3)^2=8
x-3=2√2或x-3=-2√2
x=3+2√2或x=3-2√2
2x^2-x=6
2x^2-x-6=0
(2x+3)(x-2)=0
x=-3/2或x=2
4x^2-3x-1=x-2
4x^2-4x+1=0
(2x-1)^2=0
2x-1=0
x=1/2