EQUAZIONE DELLA CIRCONFERENZA

r = 3 (slider from 0 to 4, step 0.5)
p = 2 (slider from -3 to 3, step 0.1)
q = 0 (slider from -3 to 3, step 0.1)
O = (0, 0)
C: (p, q)
c: p^(2) + q^(2) - r^(2)
a: (-2 * p)
b: (-2 * q)
d = Circle(C, r)
testo2: "" + d + ""
g(x, y) = x^(2) + y^(2)
e: x^(2) + y^(2) + (a * x) + (b * y) + c = 0
i(x, y) = (a * x) + (b * y) + c
h(x, y) = g(x, y) + i(x, y)
testo3: "" + h + "=0"