y = f(x)

Tangent

Secant

f(x) = (24 * sqrt(x + 1)) - (2 * x) - 60
A = Point({15, f(15)})
x0 = 52.05 (slider from 15 to 80)
B = Point({x0, f(x0)})
g = Tangent(A, f)
h = Line(A, B)