Metamath Proof Explorer


Theorem int-eqmvtd

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

Ref Expression
Hypotheses int-eqmvtd.1 ⊢ φ → C ∈ ℝ
int-eqmvtd.2 ⊢ φ → D ∈ ℝ
int-eqmvtd.3 ⊢ φ → A = B
int-eqmvtd.4 ⊢ φ → A = C + D
Assertion int-eqmvtd ⊢ φ → C = B − D

Proof

Step Hyp Ref Expression
1 int-eqmvtd.1 ⊢ φ → C ∈ ℝ
2 int-eqmvtd.2 ⊢ φ → D ∈ ℝ
3 int-eqmvtd.3 ⊢ φ → A = B
4 int-eqmvtd.4 ⊢ φ → A = C + D
5 3 4 eqtr3d ⊢ φ → B = C + D
6 5 oveq1d ⊢ φ → B − D = C + D - D
7 1 recnd ⊢ φ → C ∈ ℂ
8 2 recnd ⊢ φ → D ∈ ℂ
9 7 8 pncand ⊢ φ → C + D - D = C
10 6 9 eqtrd ⊢ φ → B − D = C
11 10 eqcomd ⊢ φ → C = B − D