Metamath Proof Explorer


Theorem int-eqmvtd

Description: EquMoveTerm generator rule. (Contributed by Stanislas Polu, 7-Apr-2020)

Ref Expression
Hypotheses int-eqmvtd.1
|- ( ph -> C e. RR )
int-eqmvtd.2
|- ( ph -> D e. RR )
int-eqmvtd.3
|- ( ph -> A = B )
int-eqmvtd.4
|- ( ph -> A = ( C + D ) )
Assertion int-eqmvtd
|- ( ph -> C = ( B - D ) )

Proof

Step Hyp Ref Expression
1 int-eqmvtd.1
 |-  ( ph -> C e. RR )
2 int-eqmvtd.2
 |-  ( ph -> D e. RR )
3 int-eqmvtd.3
 |-  ( ph -> A = B )
4 int-eqmvtd.4
 |-  ( ph -> A = ( C + D ) )
5 3 4 eqtr3d
 |-  ( ph -> B = ( C + D ) )
6 5 oveq1d
 |-  ( ph -> ( B - D ) = ( ( C + D ) - D ) )
7 1 recnd
 |-  ( ph -> C e. CC )
8 2 recnd
 |-  ( ph -> D e. CC )
9 7 8 pncand
 |-  ( ph -> ( ( C + D ) - D ) = C )
10 6 9 eqtrd
 |-  ( ph -> ( B - D ) = C )
11 10 eqcomd
 |-  ( ph -> C = ( B - D ) )