a = -1.15 (slider from -10 to 5, step 0.01)
c: x^(2.0) + (y - 2.0)^(2.0) = a^(2.0)
b: y = a + 3.0
y = a + 2: y = a + 3.0
A, B = Intersect(c, y = a + 2)