a = 10 (slider from -10 to 20, step 0.1)
f(x) = a / x
g(x) = 1 / x
A = Point(xAxis)
h = OrthogonalLine(A, xAxis)
B = Intersect(f, h, (2, 5))
C = Intersect(g, h, (2, 0.5))
b = Distance(B, A)
c = Distance(C, A)
texte1: "\frac{BA}{CA}=\frac{" + (LaTeX[b]) + "}{" + (LaTeX[c]) + "}=" + (LaTeX[b / c]) + ""