Distance from lamp

a = 11.4 (slider from 0 to 20, step 0.1)
HEAD: (a, 6)
FEET: (a, 0)
b = Segment(HEAD, FEET)
LAMP = (0, 18)
LAMP2 = (0, 0)
c = Segment(LAMP, LAMP2)
d = Line(LAMP, HEAD)
S = Intersect(d, e)
f = Segment(FEET, S)
A = (16.031633498187567, 10.877618629919775)
g = Circle(LAMP, A)
B = Point(f)
poly1, s, b_1, head = Polygon(B, HEAD, S)
h = Segment(LAMP, HEAD)
text1: "Shadow Length = " + f + " feet"