Metamath Proof Explorer


Theorem cnapbmcpd

Description: ((a+b)-c)+d = ((a+d)+b)-c holds for complex numbers a,b,c,d. (Contributed by Alexander van der Vekens, 23-Mar-2018)

Ref Expression
Assertion cnapbmcpd ABCDA+B-C+D=A+D+B-C

Proof

Step Hyp Ref Expression
1 addcl ABA+B
2 1 adantr ABCDA+B
3 simpr CDD
4 3 adantl ABCDD
5 simpl CDC
6 5 adantl ABCDC
7 2 4 6 addsubd ABCDA+B+D-C=A+B-C+D
8 simpl ABA
9 8 adantr ABCDA
10 simpr ABB
11 10 adantr ABCDB
12 9 11 4 add32d ABCDA+B+D=A+D+B
13 12 oveq1d ABCDA+B+D-C=A+D+B-C
14 7 13 eqtr3d ABCDA+B-C+D=A+D+B-C