| Step | Hyp | Ref | Expression | 
						
							| 1 |  | 5oalem2.1 | ⊢ 𝐴  ∈   Sℋ | 
						
							| 2 |  | 5oalem2.2 | ⊢ 𝐵  ∈   Sℋ | 
						
							| 3 |  | 5oalem2.3 | ⊢ 𝐶  ∈   Sℋ | 
						
							| 4 |  | 5oalem2.4 | ⊢ 𝐷  ∈   Sℋ | 
						
							| 5 | 1 3 | shsvsi | ⊢ ( ( 𝑥  ∈  𝐴  ∧  𝑧  ∈  𝐶 )  →  ( 𝑥  −ℎ  𝑧 )  ∈  ( 𝐴  +ℋ  𝐶 ) ) | 
						
							| 6 | 5 | ad2ant2r | ⊢ ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑧  ∈  𝐶  ∧  𝑤  ∈  𝐷 ) )  →  ( 𝑥  −ℎ  𝑧 )  ∈  ( 𝐴  +ℋ  𝐶 ) ) | 
						
							| 7 | 6 | adantr | ⊢ ( ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑧  ∈  𝐶  ∧  𝑤  ∈  𝐷 ) )  ∧  ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 ) )  →  ( 𝑥  −ℎ  𝑧 )  ∈  ( 𝐴  +ℋ  𝐶 ) ) | 
						
							| 8 | 4 2 | shsvsi | ⊢ ( ( 𝑤  ∈  𝐷  ∧  𝑦  ∈  𝐵 )  →  ( 𝑤  −ℎ  𝑦 )  ∈  ( 𝐷  +ℋ  𝐵 ) ) | 
						
							| 9 | 8 | ancoms | ⊢ ( ( 𝑦  ∈  𝐵  ∧  𝑤  ∈  𝐷 )  →  ( 𝑤  −ℎ  𝑦 )  ∈  ( 𝐷  +ℋ  𝐵 ) ) | 
						
							| 10 | 2 4 | shscomi | ⊢ ( 𝐵  +ℋ  𝐷 )  =  ( 𝐷  +ℋ  𝐵 ) | 
						
							| 11 | 9 10 | eleqtrrdi | ⊢ ( ( 𝑦  ∈  𝐵  ∧  𝑤  ∈  𝐷 )  →  ( 𝑤  −ℎ  𝑦 )  ∈  ( 𝐵  +ℋ  𝐷 ) ) | 
						
							| 12 | 11 | ad2ant2l | ⊢ ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑧  ∈  𝐶  ∧  𝑤  ∈  𝐷 ) )  →  ( 𝑤  −ℎ  𝑦 )  ∈  ( 𝐵  +ℋ  𝐷 ) ) | 
						
							| 13 | 12 | adantr | ⊢ ( ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑧  ∈  𝐶  ∧  𝑤  ∈  𝐷 ) )  ∧  ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 ) )  →  ( 𝑤  −ℎ  𝑦 )  ∈  ( 𝐵  +ℋ  𝐷 ) ) | 
						
							| 14 | 1 | sheli | ⊢ ( 𝑥  ∈  𝐴  →  𝑥  ∈   ℋ ) | 
						
							| 15 | 2 | sheli | ⊢ ( 𝑦  ∈  𝐵  →  𝑦  ∈   ℋ ) | 
						
							| 16 | 14 15 | anim12i | ⊢ ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  →  ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ ) ) | 
						
							| 17 | 3 | sheli | ⊢ ( 𝑧  ∈  𝐶  →  𝑧  ∈   ℋ ) | 
						
							| 18 | 4 | sheli | ⊢ ( 𝑤  ∈  𝐷  →  𝑤  ∈   ℋ ) | 
						
							| 19 | 17 18 | anim12i | ⊢ ( ( 𝑧  ∈  𝐶  ∧  𝑤  ∈  𝐷 )  →  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) ) | 
						
							| 20 | 16 19 | anim12i | ⊢ ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑧  ∈  𝐶  ∧  𝑤  ∈  𝐷 ) )  →  ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) ) ) | 
						
							| 21 |  | oveq1 | ⊢ ( ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 )  →  ( ( 𝑥  +ℎ  𝑦 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( ( 𝑧  +ℎ  𝑤 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) ) ) | 
						
							| 22 | 21 | adantl | ⊢ ( ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  ∧  ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 ) )  →  ( ( 𝑥  +ℎ  𝑦 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( ( 𝑧  +ℎ  𝑤 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) ) ) | 
						
							| 23 |  | simpr | ⊢ ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  →  𝑦  ∈   ℋ ) | 
						
							| 24 | 23 | anim2i | ⊢ ( ( 𝑧  ∈   ℋ  ∧  ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ ) )  →  ( 𝑧  ∈   ℋ  ∧  𝑦  ∈   ℋ ) ) | 
						
							| 25 | 24 | ancoms | ⊢ ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  𝑧  ∈   ℋ )  →  ( 𝑧  ∈   ℋ  ∧  𝑦  ∈   ℋ ) ) | 
						
							| 26 |  | hvsub4 | ⊢ ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  ( 𝑧  ∈   ℋ  ∧  𝑦  ∈   ℋ ) )  →  ( ( 𝑥  +ℎ  𝑦 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( ( 𝑥  −ℎ  𝑧 )  +ℎ  ( 𝑦  −ℎ  𝑦 ) ) ) | 
						
							| 27 | 25 26 | syldan | ⊢ ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  𝑧  ∈   ℋ )  →  ( ( 𝑥  +ℎ  𝑦 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( ( 𝑥  −ℎ  𝑧 )  +ℎ  ( 𝑦  −ℎ  𝑦 ) ) ) | 
						
							| 28 |  | hvsubid | ⊢ ( 𝑦  ∈   ℋ  →  ( 𝑦  −ℎ  𝑦 )  =  0ℎ ) | 
						
							| 29 | 28 | oveq2d | ⊢ ( 𝑦  ∈   ℋ  →  ( ( 𝑥  −ℎ  𝑧 )  +ℎ  ( 𝑦  −ℎ  𝑦 ) )  =  ( ( 𝑥  −ℎ  𝑧 )  +ℎ  0ℎ ) ) | 
						
							| 30 | 29 | ad2antlr | ⊢ ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  𝑧  ∈   ℋ )  →  ( ( 𝑥  −ℎ  𝑧 )  +ℎ  ( 𝑦  −ℎ  𝑦 ) )  =  ( ( 𝑥  −ℎ  𝑧 )  +ℎ  0ℎ ) ) | 
						
							| 31 |  | hvsubcl | ⊢ ( ( 𝑥  ∈   ℋ  ∧  𝑧  ∈   ℋ )  →  ( 𝑥  −ℎ  𝑧 )  ∈   ℋ ) | 
						
							| 32 |  | ax-hvaddid | ⊢ ( ( 𝑥  −ℎ  𝑧 )  ∈   ℋ  →  ( ( 𝑥  −ℎ  𝑧 )  +ℎ  0ℎ )  =  ( 𝑥  −ℎ  𝑧 ) ) | 
						
							| 33 | 31 32 | syl | ⊢ ( ( 𝑥  ∈   ℋ  ∧  𝑧  ∈   ℋ )  →  ( ( 𝑥  −ℎ  𝑧 )  +ℎ  0ℎ )  =  ( 𝑥  −ℎ  𝑧 ) ) | 
						
							| 34 | 33 | adantlr | ⊢ ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  𝑧  ∈   ℋ )  →  ( ( 𝑥  −ℎ  𝑧 )  +ℎ  0ℎ )  =  ( 𝑥  −ℎ  𝑧 ) ) | 
						
							| 35 | 27 30 34 | 3eqtrd | ⊢ ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  𝑧  ∈   ℋ )  →  ( ( 𝑥  +ℎ  𝑦 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( 𝑥  −ℎ  𝑧 ) ) | 
						
							| 36 | 35 | adantrr | ⊢ ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  →  ( ( 𝑥  +ℎ  𝑦 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( 𝑥  −ℎ  𝑧 ) ) | 
						
							| 37 | 36 | adantr | ⊢ ( ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  ∧  ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 ) )  →  ( ( 𝑥  +ℎ  𝑦 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( 𝑥  −ℎ  𝑧 ) ) | 
						
							| 38 |  | simpr | ⊢ ( ( 𝑦  ∈   ℋ  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  →  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) ) | 
						
							| 39 |  | simpl | ⊢ ( ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ )  →  𝑧  ∈   ℋ ) | 
						
							| 40 | 39 | anim1i | ⊢ ( ( ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ )  ∧  𝑦  ∈   ℋ )  →  ( 𝑧  ∈   ℋ  ∧  𝑦  ∈   ℋ ) ) | 
						
							| 41 | 40 | ancoms | ⊢ ( ( 𝑦  ∈   ℋ  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  →  ( 𝑧  ∈   ℋ  ∧  𝑦  ∈   ℋ ) ) | 
						
							| 42 |  | hvsub4 | ⊢ ( ( ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ )  ∧  ( 𝑧  ∈   ℋ  ∧  𝑦  ∈   ℋ ) )  →  ( ( 𝑧  +ℎ  𝑤 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( ( 𝑧  −ℎ  𝑧 )  +ℎ  ( 𝑤  −ℎ  𝑦 ) ) ) | 
						
							| 43 | 38 41 42 | syl2anc | ⊢ ( ( 𝑦  ∈   ℋ  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  →  ( ( 𝑧  +ℎ  𝑤 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( ( 𝑧  −ℎ  𝑧 )  +ℎ  ( 𝑤  −ℎ  𝑦 ) ) ) | 
						
							| 44 |  | hvsubid | ⊢ ( 𝑧  ∈   ℋ  →  ( 𝑧  −ℎ  𝑧 )  =  0ℎ ) | 
						
							| 45 | 44 | oveq1d | ⊢ ( 𝑧  ∈   ℋ  →  ( ( 𝑧  −ℎ  𝑧 )  +ℎ  ( 𝑤  −ℎ  𝑦 ) )  =  ( 0ℎ  +ℎ  ( 𝑤  −ℎ  𝑦 ) ) ) | 
						
							| 46 | 45 | ad2antrl | ⊢ ( ( 𝑦  ∈   ℋ  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  →  ( ( 𝑧  −ℎ  𝑧 )  +ℎ  ( 𝑤  −ℎ  𝑦 ) )  =  ( 0ℎ  +ℎ  ( 𝑤  −ℎ  𝑦 ) ) ) | 
						
							| 47 |  | hvsubcl | ⊢ ( ( 𝑤  ∈   ℋ  ∧  𝑦  ∈   ℋ )  →  ( 𝑤  −ℎ  𝑦 )  ∈   ℋ ) | 
						
							| 48 |  | hvaddlid | ⊢ ( ( 𝑤  −ℎ  𝑦 )  ∈   ℋ  →  ( 0ℎ  +ℎ  ( 𝑤  −ℎ  𝑦 ) )  =  ( 𝑤  −ℎ  𝑦 ) ) | 
						
							| 49 | 47 48 | syl | ⊢ ( ( 𝑤  ∈   ℋ  ∧  𝑦  ∈   ℋ )  →  ( 0ℎ  +ℎ  ( 𝑤  −ℎ  𝑦 ) )  =  ( 𝑤  −ℎ  𝑦 ) ) | 
						
							| 50 | 49 | ancoms | ⊢ ( ( 𝑦  ∈   ℋ  ∧  𝑤  ∈   ℋ )  →  ( 0ℎ  +ℎ  ( 𝑤  −ℎ  𝑦 ) )  =  ( 𝑤  −ℎ  𝑦 ) ) | 
						
							| 51 | 50 | adantrl | ⊢ ( ( 𝑦  ∈   ℋ  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  →  ( 0ℎ  +ℎ  ( 𝑤  −ℎ  𝑦 ) )  =  ( 𝑤  −ℎ  𝑦 ) ) | 
						
							| 52 | 43 46 51 | 3eqtrd | ⊢ ( ( 𝑦  ∈   ℋ  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  →  ( ( 𝑧  +ℎ  𝑤 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( 𝑤  −ℎ  𝑦 ) ) | 
						
							| 53 | 52 | adantll | ⊢ ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  →  ( ( 𝑧  +ℎ  𝑤 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( 𝑤  −ℎ  𝑦 ) ) | 
						
							| 54 | 53 | adantr | ⊢ ( ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  ∧  ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 ) )  →  ( ( 𝑧  +ℎ  𝑤 )  −ℎ  ( 𝑧  +ℎ  𝑦 ) )  =  ( 𝑤  −ℎ  𝑦 ) ) | 
						
							| 55 | 22 37 54 | 3eqtr3d | ⊢ ( ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  ∧  ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 ) )  →  ( 𝑥  −ℎ  𝑧 )  =  ( 𝑤  −ℎ  𝑦 ) ) | 
						
							| 56 | 55 | eleq1d | ⊢ ( ( ( ( 𝑥  ∈   ℋ  ∧  𝑦  ∈   ℋ )  ∧  ( 𝑧  ∈   ℋ  ∧  𝑤  ∈   ℋ ) )  ∧  ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 ) )  →  ( ( 𝑥  −ℎ  𝑧 )  ∈  ( 𝐵  +ℋ  𝐷 )  ↔  ( 𝑤  −ℎ  𝑦 )  ∈  ( 𝐵  +ℋ  𝐷 ) ) ) | 
						
							| 57 | 20 56 | sylan | ⊢ ( ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑧  ∈  𝐶  ∧  𝑤  ∈  𝐷 ) )  ∧  ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 ) )  →  ( ( 𝑥  −ℎ  𝑧 )  ∈  ( 𝐵  +ℋ  𝐷 )  ↔  ( 𝑤  −ℎ  𝑦 )  ∈  ( 𝐵  +ℋ  𝐷 ) ) ) | 
						
							| 58 | 13 57 | mpbird | ⊢ ( ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑧  ∈  𝐶  ∧  𝑤  ∈  𝐷 ) )  ∧  ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 ) )  →  ( 𝑥  −ℎ  𝑧 )  ∈  ( 𝐵  +ℋ  𝐷 ) ) | 
						
							| 59 | 7 58 | elind | ⊢ ( ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑧  ∈  𝐶  ∧  𝑤  ∈  𝐷 ) )  ∧  ( 𝑥  +ℎ  𝑦 )  =  ( 𝑧  +ℎ  𝑤 ) )  →  ( 𝑥  −ℎ  𝑧 )  ∈  ( ( 𝐴  +ℋ  𝐶 )  ∩  ( 𝐵  +ℋ  𝐷 ) ) ) |