y=3-x^2

y=x-3

y=ax+b

f = Function(3 - x^(2), -1000, -1)
g = Function(x - 3, 3, 1000)
a = 0.8 (slider from -5 to 5, step 0.1)
b = 0 (slider from -5 to 5, step 0.1)
h = Function(a * x + b, -1, 3)
A = Point(f)
B = Point(h)
C = Point(g)