have : x ≃ (-a) / b := x_eqv_neg_a_over_b
ℚ : Type
inst✝ : Rational ℚ
x : ℚ
x✝ : AltNegative x
a b : ℤ
a_pos✝ : AP (Positive a)
b_pos✝ : AP (Positive b)
x_eqv_neg_a_over_b : x ≃ -Rational.from_integer a / Rational.from_integer b
⊢ Negative x
ℚ : Type
inst✝ : Rational ℚ
x : ℚ
x✝ : AltNegative x
a b : ℤ
a_pos✝ : AP (Positive a)
b_pos✝ : AP (Positive b)
x_eqv_neg_a_over_b this : x ≃ -Rational.from_integer a / Rational.from_integer b
⊢ Negative x