x2−4x+5=0x^{2}-4 x+5=0x2−4x+5=0
x2+4x−3=0x^{2}+4 x-3=0x2+4x−3=0
x2−4x+3=0x^{2}-4 x+3=0x2−4x+3=0
x2+4x−5=0x^{2}+4 x-5=0x2+4x−5=0