Metamath Proof Explorer


Theorem decaddcom

Description: Commute ones place in addition. (Contributed by Steven Nguyen, 29-Jan-2023)

Ref Expression
Hypotheses decaddcom.a
|- A e. NN0
decaddcom.b
|- B e. NN0
decaddcom.c
|- C e. NN0
Assertion decaddcom
|- ( ; A B + C ) = ( ; A C + B )

Proof

Step Hyp Ref Expression
1 decaddcom.a
 |-  A e. NN0
2 decaddcom.b
 |-  B e. NN0
3 decaddcom.c
 |-  C e. NN0
4 eqid
 |-  ; A B = ; A B
5 eqid
 |-  ( B + C ) = ( B + C )
6 1 2 3 4 5 decaddi
 |-  ( ; A B + C ) = ; A ( B + C )
7 eqid
 |-  ; A C = ; A C
8 3 nn0cni
 |-  C e. CC
9 2 nn0cni
 |-  B e. CC
10 8 9 addcomi
 |-  ( C + B ) = ( B + C )
11 1 3 2 7 10 decaddi
 |-  ( ; A C + B ) = ; A ( B + C )
12 6 11 eqtr4i
 |-  ( ; A B + C ) = ( ; A C + B )