x2+4x−6=0x^{2}+4 x-6=0x2+4x−6=0
x2−4x−6=0x^{2-} 4 x-6=0x2−4x−6=0
x2−4x+6=0x^{2}-4 x+6=0x2−4x+6=0
x2+4x+6=0x^{2}+4 x+6=0x2+4x+6=0
