Pour chacune des figures, tu dois décider si :
(DG) et (BC) sont perpendiculaires ;
(DG) et (EF) sont parallèles.

Figure bleue n° 1

Figure verte n° 2

Figure rose n° 3

A

B

C

D

E

F

G

A

B

C

D

E

F

G

B = (0, 1)
C = (6, 1)
A_1 = (3, 8)
a = Segment(A_1, B)
b = Segment(B, C)
c = Segment(C, A_1)
D = Point(b)
E_1 = Point(b)
d = OrthogonalLine(D, b)
F = Point(c)
G = Intersect(d, a)
e = Segment(G, F)
f = Segment(F, E_1)
g = Segment(G, D)
B' = (14.38, -0.04)
C' = (20.76, 2.7)
h = LineBisector(B', C')
A' = Point(h)
i = Segment(B', C')
D' = Point(i)
j = Segment(A', B')
k = Segment(C', A')
G' = Point(j)
l = Line(G', i)
F' = Intersect(l, k)
m = Segment(G', D')
n = Line(F', m)
E' = Intersect(n, i)
p = Segment(G', F')
q = Segment(F', E')
B'' = (5.83, -2.498)
C'' = (10.078, -5.284)
A'' = (11.062, 0.8260000000000016)
r = Segment(B'', C'')
s = Segment(C'', A'')
t = Segment(A'', B'')
D'' = Point(r)
a_1 = OrthogonalLine(D'', r)
G'' = Intersect(a_1, t)
M = Midpoint(B'', C'')
E'' = Mirror(D'', M)
b_1 = OrthogonalLine(E'', r)
F'' = Intersect(b_1, s)
c_1 = Segment(G'', D'')
d_1 = Segment(F'', G'')
e_1 = Segment(F'', E'')