A = Intersect(xAxis, yAxis)
B = Point(xAxis)
C = (4, 5)
a = Segment(C, B)
b = Segment(A, B)
c = Segment(A, C)
d = 2.5 (slider from 0 to 5, step 0.1)
M: (4, d)
e = Line(M, xAxis)
N = Intersect(c, e)
poly1, n, a_1, m = Polygon(A, M, N)
Textepoly1: "Aire " + (Name[A]) + (Name[M]) + (Name[N]) + " = " + poly1
T1: "x = " + d