-х^{2}+4х-3=0

2 x^{2} +4х=0

-2 x^{2} +4х+6=0

3)-x²+4x-3=02x²+4x=0-2x²+4x+6=0-2(x²-2x-3)=0-2(-x²+x-3x-3)=0-2(x(x+1)-3(x+1)=0-2(x-3)(x+1)=0(x-3)(x+1)=0x-3=0x+1=0x=3x=-1x1=3;x2=-1