Radius of Circle

r = 1.5 (slider from 0.5 to 3, step 0.25)
A: (r, 0.0)
B = Intersect(xAxis, yAxis)
c = Circle(B, A)
C = Point(c)
α = Angle(A, B, C)
a = Segment(B, C)
text3: "Y-Coordinate of Point  =  y  =  " + (y(C))
text2: "X-Coordinate of Point  =  x =   " + (x(C))
text5: "Cos(θ) = x / r  = ADJ / HYP = " + (x(C) / r)
text4: "Sin(θ) = y / r = OPP / HYP = " + (y(C) / r)
D: (x(C), 0.0)
b = Segment(D, C)
d = Segment(B, D)
text6: "Tan(θ) = y / x  = OPP / ADJ =  " + (y(C) / x(C))
E = (3.8, 1.7)
F = (3.8, 0.1)
G = (7.7, 0.1)
H = (7.7, 1.7)
poly1, e, f, g, h = Polygon(E, F, G, H)