b = 3 (slider from 1 to 50, step 1)
A = Point(xAxis)
B: (b, 0)
O = (0, 0)
c = Semicircle(A, B)
T = Intersect(c, yAxis)
distanceOB = Distance(O, B)
Midpoint(O, B)
TexteOB: Name[O] + (Name[B]) + " \, = \, " + distanceOB
distanceOT = Distance(O, T)
Midpoint(O, T)
TexteOT: Name[O] + (Name[T]) + " \, = \, " + distanceOT