Metamath Proof Explorer


Theorem cgrsub

Description: Removing identical parts from the end of a line segment preserves congruence. Theorem 4.3 of Schwabhauser p. 35. (Contributed by Scott Fenton, 4-Oct-2013)

Ref Expression
Assertion cgrsub N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A B Cgr D E

Proof

Step Hyp Ref Expression
1 simprl N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F B Btwn A C E Btwn D F
2 simprr N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A C Cgr D F B C Cgr E F
3 simpl1 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F N
4 simpl21 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A 𝔼 N
5 simpl31 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F D 𝔼 N
6 cgrtriv N A 𝔼 N D 𝔼 N A A Cgr D D
7 3 4 5 6 syl3anc N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A A Cgr D D
8 simprrl N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A C Cgr D F
9 simpl23 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F C 𝔼 N
10 simpl33 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F F 𝔼 N
11 cgrcomlr N A 𝔼 N C 𝔼 N D 𝔼 N F 𝔼 N A C Cgr D F C A Cgr F D
12 3 4 9 5 10 11 syl122anc N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A C Cgr D F C A Cgr F D
13 8 12 mpbid N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F C A Cgr F D
14 7 13 jca N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A A Cgr D D C A Cgr F D
15 simpl22 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F B 𝔼 N
16 simpl32 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F E 𝔼 N
17 brifs N A 𝔼 N B 𝔼 N C 𝔼 N A 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N D 𝔼 N A B C A InnerFiveSeg D E F D B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A A Cgr D D C A Cgr F D
18 ifscgr N A 𝔼 N B 𝔼 N C 𝔼 N A 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N D 𝔼 N A B C A InnerFiveSeg D E F D B A Cgr E D
19 17 18 sylbird N A 𝔼 N B 𝔼 N C 𝔼 N A 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N D 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A A Cgr D D C A Cgr F D B A Cgr E D
20 3 4 15 9 4 5 16 10 5 19 syl333anc N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A A Cgr D D C A Cgr F D B A Cgr E D
21 1 2 14 20 mp3and N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F B A Cgr E D
22 cgrcomlr N B 𝔼 N A 𝔼 N E 𝔼 N D 𝔼 N B A Cgr E D A B Cgr D E
23 3 15 4 16 5 22 syl122anc N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F B A Cgr E D A B Cgr D E
24 21 23 mpbid N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A B Cgr D E
25 24 ex N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B Btwn A C E Btwn D F A C Cgr D F B C Cgr E F A B Cgr D E