Metamath Proof Explorer


Theorem midofsegid

Description: If two points fall in the same place in the middle of a segment, then they are identical. (Contributed by Scott Fenton, 16-Oct-2013) (Revised by Mario Carneiro, 19-Apr-2014)

Ref Expression
Assertion midofsegid N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D = E

Proof

Step Hyp Ref Expression
1 simp1 N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N N
2 simp2l N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N A 𝔼 N
3 simp3r N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N E 𝔼 N
4 simp3l N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D 𝔼 N
5 simprr N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D Btwn A E D Btwn A E
6 simprl3 N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D Btwn A E A D Cgr A E
7 1 2 4 2 3 6 cgrcomand N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D Btwn A E A E Cgr A D
8 1 2 3 4 5 7 endofsegidand N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D Btwn A E E = D
9 8 eqcomd N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D Btwn A E D = E
10 9 expr N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D Btwn A E D = E
11 simprr N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E E Btwn A D E Btwn A D
12 simprl3 N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E E Btwn A D A D Cgr A E
13 1 2 4 3 11 12 endofsegidand N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E E Btwn A D D = E
14 13 expr N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E E Btwn A D D = E
15 3simpa D Btwn A B E Btwn A B A D Cgr A E D Btwn A B E Btwn A B
16 15 adantl N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D Btwn A B E Btwn A B
17 simp2r N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N B 𝔼 N
18 btwnconn3 N A 𝔼 N D 𝔼 N E 𝔼 N B 𝔼 N D Btwn A B E Btwn A B D Btwn A E E Btwn A D
19 1 2 4 3 17 18 syl122anc N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B D Btwn A E E Btwn A D
20 19 adantr N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D Btwn A B E Btwn A B D Btwn A E E Btwn A D
21 16 20 mpd N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D Btwn A E E Btwn A D
22 10 14 21 mpjaod N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D = E
23 22 ex N A 𝔼 N B 𝔼 N D 𝔼 N E 𝔼 N D Btwn A B E Btwn A B A D Cgr A E D = E