Metamath Proof Explorer


Theorem subge02d

Description: Nonnegative subtraction. (Contributed by Mario Carneiro, 27-May-2016)

Ref Expression
Hypotheses leidd.1 ⊢ φ → A ∈ ℝ
ltnegd.2 ⊢ φ → B ∈ ℝ
Assertion subge02d ⊢ φ → 0 ≤ B ↔ A − B ≤ A

Proof

Step Hyp Ref Expression
1 leidd.1 ⊢ φ → A ∈ ℝ
2 ltnegd.2 ⊢ φ → B ∈ ℝ
3 subge02 ⊢ A ∈ ℝ ∧ B ∈ ℝ → 0 ≤ B ↔ A − B ≤ A
4 1 2 3 syl2anc ⊢ φ → 0 ≤ B ↔ A − B ≤ A