B = (19.720505629578636, -8.012236786469346)
D = (-4.858003834996802, -7.989201632331974)
E = (-4.858003834996802, 9.379304587246185)
a = -0.1 (slider from -6 to 3, step 0.1)
b = 1.8 (slider from 0 to 8, step 0.1)
c = -1.1 (slider from -5 to 5, step 0.1)
f(x) = a * x^(2.0) + b * x + c