Metamath Proof Explorer


Theorem lnhl

Description: Either a point C on the line AB is on the same side as A or on the opposite side. (Contributed by Thierry Arnoux, 21-Sep-2020)

Ref Expression
Hypotheses ishlg.p P = Base G
ishlg.i I = Itv G
ishlg.k K = hl 𝒢 G
ishlg.a φ A P
ishlg.b φ B P
ishlg.c φ C P
hlln.1 φ G 𝒢 Tarski
hltr.d φ D P
lnhl.l L = Line 𝒢 G
lnhl.1 φ C A L B
Assertion lnhl φ C K B A B A I C

Proof

Step Hyp Ref Expression
1 ishlg.p P = Base G
2 ishlg.i I = Itv G
3 ishlg.k K = hl 𝒢 G
4 ishlg.a φ A P
5 ishlg.b φ B P
6 ishlg.c φ C P
7 hlln.1 φ G 𝒢 Tarski
8 hltr.d φ D P
9 lnhl.l L = Line 𝒢 G
10 lnhl.1 φ C A L B
11 simpr φ C = B C = B
12 eqid dist G = dist G
13 1 12 2 7 4 6 tgbtwntriv2 φ C A I C
14 13 adantr φ C = B C A I C
15 11 14 eqeltrrd φ C = B B A I C
16 15 olcd φ C = B C K B A B A I C
17 1 9 2 7 4 5 10 tglngne φ A B
18 1 9 2 7 4 5 17 6 tgellng φ C A L B C A I B A C I B B A I C
19 10 18 mpbid φ C A I B A C I B B A I C
20 df-3or C A I B A C I B B A I C C A I B A C I B B A I C
21 19 20 sylib φ C A I B A C I B B A I C
22 21 adantr φ C B C A I B A C I B B A I C
23 1 2 3 6 4 5 7 ishlg φ C K B A C B A B C B I A A B I C
24 23 adantr φ C B C K B A C B A B C B I A A B I C
25 df-3an C B A B C B I A A B I C C B A B C B I A A B I C
26 24 25 bitrdi φ C B C K B A C B A B C B I A A B I C
27 17 anim1ci φ C B C B A B
28 27 biantrurd φ C B C B I A A B I C C B A B C B I A A B I C
29 7 adantr φ C B G 𝒢 Tarski
30 5 adantr φ C B B P
31 6 adantr φ C B C P
32 4 adantr φ C B A P
33 1 12 2 29 30 31 32 tgbtwncomb φ C B C B I A C A I B
34 1 12 2 29 30 32 31 tgbtwncomb φ C B A B I C A C I B
35 33 34 orbi12d φ C B C B I A A B I C C A I B A C I B
36 26 28 35 3bitr2d φ C B C K B A C A I B A C I B
37 36 orbi1d φ C B C K B A B A I C C A I B A C I B B A I C
38 22 37 mpbird φ C B C K B A B A I C
39 16 38 pm2.61dane φ C K B A B A I C