Theorem: Set.inter_subset_left (GMLInit/Data/Set/Subset.lean)

State before:
α : Sort u_1
s✝ t✝ u s t : Set α
⊢ (s.inter t).Subset s
Tactic:
intro x ⟨hs,_⟩
State after:
α : Sort u_1
s✝ t✝ u s t : Set α
x : α
hs : x ∈ s
right✝ : x ∈ t
⊢ x ∈ s

State before:
α : Sort u_1
s✝ t✝ u s t : Set α
x : α
hs : x ∈ s
right✝ : x ∈ t
⊢ x ∈ s
Tactic:
exact hs
State after:
no goals