Metamath Proof Explorer


Theorem ablsubsub23

Description: Swap subtrahend and result of group subtraction. (Contributed by NM, 14-Dec-2007) (Revised by AV, 7-Oct-2021)

Ref Expression
Hypotheses ablsubsub23.v V = Base G
ablsubsub23.m - ˙ = - G
Assertion ablsubsub23 G Abel A V B V C V A - ˙ B = C A - ˙ C = B

Proof

Step Hyp Ref Expression
1 ablsubsub23.v V = Base G
2 ablsubsub23.m - ˙ = - G
3 simpl G Abel A V B V C V G Abel
4 simpr3 G Abel A V B V C V C V
5 simpr2 G Abel A V B V C V B V
6 eqid + G = + G
7 1 6 ablcom G Abel C V B V C + G B = B + G C
8 3 4 5 7 syl3anc G Abel A V B V C V C + G B = B + G C
9 8 eqeq1d G Abel A V B V C V C + G B = A B + G C = A
10 ablgrp G Abel G Grp
11 1 6 2 grpsubadd G Grp A V B V C V A - ˙ B = C C + G B = A
12 10 11 sylan G Abel A V B V C V A - ˙ B = C C + G B = A
13 3ancomb A V B V C V A V C V B V
14 13 biimpi A V B V C V A V C V B V
15 1 6 2 grpsubadd G Grp A V C V B V A - ˙ C = B B + G C = A
16 10 14 15 syl2an G Abel A V B V C V A - ˙ C = B B + G C = A
17 9 12 16 3bitr4d G Abel A V B V C V A - ˙ B = C A - ˙ C = B