a = 0.4 (slider from -5 to 5, step 0.1)
b = -2.4 (slider from -5 to 5, step 0.1)
c = 3.1 (slider from -5 to 5, step 0.1)
d = 0.5 (slider from -5 to 5, step 0.1)
e = 0 (slider from -5 to 5, step 0.1)
f(x) = (a * x^(4)) + (b * x^(3)) + (c * x^(2)) + (d * x) + e
A, B, C, D = Intersect(f, xAxis)