Why is a positive divided by a negative equal to a negative

Why is a positive divided by a negative equal to a negative

If (x + y) divided by (a + b) is less than 0, then (x + y) multiplied by (a + b) must be less than 0, then (x + y) multiplied by (a + b) must be negative, so (x + y) / (a + B) is also less than 0