x2−x+4=0x^{2}-x+4=0x2−x+4=0
x2+4x−1=0x^{2}+4 x-1=0x2+4x−1=0
x2−4x+1=0x^{2}-4 x+1=0x2−4x+1=0
x2+x−4=0x^{2}+x-4=0x2+x−4=0