Metamath Proof Explorer


Theorem hypcgr

Description: If the catheti of two right-angled triangles are congruent, so is their hypothenuse. Theorem 10.12 of Schwabhauser p. 91. (Contributed by Thierry Arnoux, 16-Dec-2019)

Ref Expression
Hypotheses hypcgr.p P = Base G
hypcgr.m - ˙ = dist G
hypcgr.i I = Itv G
hypcgr.g φ G 𝒢 Tarski
hypcgr.h φ G Dim 𝒢 2
hypcgr.a φ A P
hypcgr.b φ B P
hypcgr.c φ C P
hypcgr.d φ D P
hypcgr.e φ E P
hypcgr.f φ F P
hypcgr.1 φ ⟨“ ABC ”⟩ 𝒢 G
hypcgr.2 φ ⟨“ DEF ”⟩ 𝒢 G
hypcgr.3 φ A - ˙ B = D - ˙ E
hypcgr.4 φ B - ˙ C = E - ˙ F
Assertion hypcgr φ A - ˙ C = D - ˙ F

Proof

Step Hyp Ref Expression
1 hypcgr.p P = Base G
2 hypcgr.m - ˙ = dist G
3 hypcgr.i I = Itv G
4 hypcgr.g φ G 𝒢 Tarski
5 hypcgr.h φ G Dim 𝒢 2
6 hypcgr.a φ A P
7 hypcgr.b φ B P
8 hypcgr.c φ C P
9 hypcgr.d φ D P
10 hypcgr.e φ E P
11 hypcgr.f φ F P
12 hypcgr.1 φ ⟨“ ABC ”⟩ 𝒢 G
13 hypcgr.2 φ ⟨“ DEF ”⟩ 𝒢 G
14 hypcgr.3 φ A - ˙ B = D - ˙ E
15 hypcgr.4 φ B - ˙ C = E - ˙ F
16 eqid Line 𝒢 G = Line 𝒢 G
17 eqid pInv 𝒢 G = pInv 𝒢 G
18 1 2 3 4 5 7 10 midcl φ B mid 𝒢 G E P
19 eqid pInv 𝒢 G B mid 𝒢 G E = pInv 𝒢 G B mid 𝒢 G E
20 1 2 3 16 17 4 18 19 9 mircl φ pInv 𝒢 G B mid 𝒢 G E D P
21 1 2 3 16 17 4 18 19 10 mircl φ pInv 𝒢 G B mid 𝒢 G E E P
22 1 2 3 16 17 4 18 19 11 mircl φ pInv 𝒢 G B mid 𝒢 G E F P
23 1 2 3 16 17 4 9 10 11 13 19 18 mirrag φ ⟨“ pInv 𝒢 G B mid 𝒢 G E D pInv 𝒢 G B mid 𝒢 G E E pInv 𝒢 G B mid 𝒢 G E F ”⟩ 𝒢 G
24 1 2 3 16 17 4 18 19 9 10 miriso φ pInv 𝒢 G B mid 𝒢 G E D - ˙ pInv 𝒢 G B mid 𝒢 G E E = D - ˙ E
25 14 24 eqtr4d φ A - ˙ B = pInv 𝒢 G B mid 𝒢 G E D - ˙ pInv 𝒢 G B mid 𝒢 G E E
26 1 2 3 16 17 4 18 19 10 11 miriso φ pInv 𝒢 G B mid 𝒢 G E E - ˙ pInv 𝒢 G B mid 𝒢 G E F = E - ˙ F
27 15 26 eqtr4d φ B - ˙ C = pInv 𝒢 G B mid 𝒢 G E E - ˙ pInv 𝒢 G B mid 𝒢 G E F
28 1 2 3 4 5 10 7 midcom φ E mid 𝒢 G B = B mid 𝒢 G E
29 1 2 3 4 5 10 7 17 18 ismidb φ B = pInv 𝒢 G B mid 𝒢 G E E E mid 𝒢 G B = B mid 𝒢 G E
30 28 29 mpbird φ B = pInv 𝒢 G B mid 𝒢 G E E
31 eqid lInv 𝒢 G C mid 𝒢 G pInv 𝒢 G B mid 𝒢 G E F Line 𝒢 G B = lInv 𝒢 G C mid 𝒢 G pInv 𝒢 G B mid 𝒢 G E F Line 𝒢 G B
32 1 2 3 4 5 6 7 8 20 21 22 12 23 25 27 30 31 hypcgrlem2 φ A - ˙ C = pInv 𝒢 G B mid 𝒢 G E D - ˙ pInv 𝒢 G B mid 𝒢 G E F
33 1 2 3 16 17 4 18 19 9 11 miriso φ pInv 𝒢 G B mid 𝒢 G E D - ˙ pInv 𝒢 G B mid 𝒢 G E F = D - ˙ F
34 32 33 eqtrd φ A - ˙ C = D - ˙ F