Metamath Proof Explorer


Theorem subcan2ad

Description: Cancellation law for subtraction. Deduction form of subcan2 . Generalization of subcan2d . (Contributed by David Moews, 28-Feb-2017)

Ref Expression
Hypotheses negidd.1 ⊢ φ → A ∈ ℂ
pncand.2 ⊢ φ → B ∈ ℂ
subaddd.3 ⊢ φ → C ∈ ℂ
Assertion subcan2ad ⊢ φ → A − C = B − C ↔ A = B

Proof

Step Hyp Ref Expression
1 negidd.1 ⊢ φ → A ∈ ℂ
2 pncand.2 ⊢ φ → B ∈ ℂ
3 subaddd.3 ⊢ φ → C ∈ ℂ
4 subcan2 ⊢ A ∈ ℂ ∧ B ∈ ℂ ∧ C ∈ ℂ → A − C = B − C ↔ A = B
5 1 2 3 4 syl3anc ⊢ φ → A − C = B − C ↔ A = B