What property is used for these problems? I believe it is the commutative property for at least the first one. n/-3 + 5 > 4 and 3a - 4 < 5 (The less than sign for the second problem is underlined.

Answer 1

You have the properties, so just look at the steps involved
n/-3 + 5 > 4
n/-3 > -1
n < 3
That last step doesn't really fit the properties, but it can be done in several parts
0 > -1 - (n/-3)
0 > -1 + n/3
1 > n/3
3 > n

the second one is even easier, since it does not involve multiplication by a negative

Answer 2

I already had the answer for that one, but thank you for helping me understand it better! Following those steps, I'm supposing the answer to the second one is a ≤ 3?