Construction in GCLC language
dim 120 120
point C 110 40
point T_{a} 70.86 40
point I 74.37 61.15
color 220 0 0
fontsize 11
cmark_b C
cmark_b T_{a}
cmark_b I
color 0 0 0
fontsize 10
% DET: points C and T_{a} are not the same
% Constructing a line a which passes through point C and point T_{a}
line a C T_{a}
color 200 200 200
drawline a
color 0 0 0
% DET: points T_{a} and I are not the same
% Constructing a line s_{a} which passes through point T_{a} and point I
line s_{a} T_{a} I
color 200 200 200
drawline s_{a}
color 0 0 0
% NDG: point I is not incident to the line a
% Constructing a point P_{\_G56460} which is a foot of the point I on the line a
foot P_{\_G56460} I a
cmark_r P_{\_G56460}
color 200 200 200
drawline I P_{\_G56460}
color 0 0 0
% Constructing a circle k(I,P_{a}) whose center is at point I and which passes through point P_{\_G56460}
circle k(I,P_{a}) I P_{\_G56460}
color 200 200 200
drawcircle k(I,P_{a})
color 0 0 0
% NDG: point C is outside the circle k(I,P_{a})
% Constructing a point P_{\_G56667} which is a foot of the point I on the line a
foot P_{\_G56667} I a
cmark_r P_{\_G56667}
color 200 200 200
drawline I P_{\_G56667}
color 0 0 0
% Constructing a line L_{\_G56670} which passes through point I and point C
line L_{\_G56670} I C
color 200 200 200
drawline L_{\_G56670}
color 0 0 0
% Constructing a point P_{\_G56673} which is an image of the point P_{\_G56667} in the symmetry to point/line L_{\_G56670}
sim P_{\_G56673} L_{\_G56670} P_{\_G56667}
cmark_r P_{\_G56673}
% Constructing a line b which passes through point C and point P_{\_G56673}
line b C P_{\_G56673}
color 200 200 200
drawline b
color 0 0 0
% NDG: lines b and s_{a} are not parallel% DET: lines b and s_{a} are not the same
% Constructing a point A which belongs to line b and line s_{a}
intersec A b s_{a}
cmark_t A
% NDG: point A is outside the circle k(I,P_{a})
% Constructing a point P_{\_G57059} which is a foot of the point I on the line b
foot P_{\_G57059} I b
cmark_r P_{\_G57059}
color 200 200 200
drawline I P_{\_G57059}
color 0 0 0
% Constructing a line L_{\_G57062} which passes through point I and point A
line L_{\_G57062} I A
color 200 200 200
drawline L_{\_G57062}
color 0 0 0
% Constructing a point P_{\_G57065} which is an image of the point P_{\_G57059} in the symmetry to point/line L_{\_G57062}
sim P_{\_G57065} L_{\_G57062} P_{\_G57059}
cmark_r P_{\_G57065}
% Constructing a line c which passes through point A and point P_{\_G57065}
line c A P_{\_G57065}
color 200 200 200
drawline c
color 0 0 0
% NDG: lines c and a are not parallel% DET: lines c and a are not the same
% Constructing a point B which belongs to line c and line a
intersec B c a
cmark_b B
drawsegment A B
drawsegment A C
drawsegment B C
% Non-degenerate conditions: lines c and a are not parallel; point A is outside the circle k(I,P_{a}); lines b and s_{a} are not parallel; point C is outside the circle k(I,P_{a}); point I is not incident to the line a
% Determination conditions: lines c and a are not the same; lines b and s_{a} are not the same; points T_{a} and I are not the same; points C and T_{a} are not the same