Construction in GCLC language

dim 120 120

point B 20 40
point O 65 51.14
point H_{a} 80 40

color 220 0 0
fontsize 11

cmark_b B
cmark_t O
cmark_b H_{a}
color 0 0 0
fontsize 10

% DET:  points B and H_{a} are not the same
% Constructing a line a which passes through point B and point H_{a}
line a B H_{a} 

color 200 200 200
drawline a
color 0 0 0



% NDG:  points B and O are not the same
% Constructing a circle k(O,C) whose center is at point O and which passes through point B
circle k(O,C) O B 

color 200 200 200
drawcircle k(O,C)
color 0 0 0



% NDG:  line a and circle k(O,C) intersect% DET:  points B and C must be different
% Constructing a point P_{\_G23376} which is a foot of the point O on the line a
foot P_{\_G23376} O a 
cmark_r P_{\_G23376}
color 200 200 200
drawline O P_{\_G23376} 
color 0 0 0

% Constructing a point C which is an image of the point B in the symmetry to point/line P_{\_G23376}
sim C P_{\_G23376} B 
cmark_b C



% Constructing a line h_{a} which is perpendicular to line a and which passes through point H_{a}
perp h_{a} H_{a} a 

color 200 200 200
drawline h_{a}
color 0 0 0



% NDG:  line h_{a} and circle k(O,C) intersect
% Constructing points A_{k} and A which are in intersection of k(O,C) and h_{a}
intersec2 A_{k} A k(O,C) h_{a} 
cmark_r A_{k}
cmark_t A



drawsegment A B
drawsegment A C
drawsegment B C

% Non-degenerate conditions:  line h_{a} and circle k(O,C) intersect; line a and circle k(O,C) intersect; points B and O are not the same
% Determination conditions:  points B and C must be different; points B and H_{a} are not the same