Answer:
It is Commutative
Step-by-step explanation:
An operation ∆ is said to be Commutative if a∆b=b∆a ∀ a,b ∈ ℝ.
Given the operation ∆ defined by:
a∆b=a X b

a∆b=
=3
Similarly, for the right hand side.

Therefore:
b∆a=
=3
These are the two ways of solving this problem and we have in fact shown that the operation is commutative as:
a∆b=b∆a=3
Negative 6 and negative 2
I believe it’s 361, tell me if I’m wrong though!
Easy, 100 x 3 is 300 pounds, 5 x 3 is 15, so 15 pounds. :)