Jika persamaan

Berarti
pusat = (-1/2.-4, -1/2.0) = (2,0)
r = √(1/4.(-4)² -c) = √(4-c)
menyinggung garis y = 1, jadi :
r = 1 – 0
√(4-c) = 1
4-c = 1
c = 3

r = √(4-3) = 1
jadi persamaannya :
(x-2)² + (y-0)² = 1²
x² -4x + 4 + y² = 1
x² + y² – 4x + 3 = 0
b = 1

b + c = 1 + 3 = 4