x2+y2−8y−1=0x^{2}+y^{2}-8 y-1=0x2+y2−8y−1=0
x2+y2−6y−1=0x^{2}+y^{2}-6 y-1=0x2+y2−6y−1=0
x2+y2−5y−7=0x^{2}+y^{2}-5 y-7=0x2+y2−5y−7=0
x2+y2−8y−9=0x^{2}+y^{2}-8 y-9=0x2+y2−8y−9=0