Algebra

The answer is -(2+2/3). This is how to work it out. From the rules of the commutative property, we can switch the 6 and the n around. 6+2/3=6 and 2/3. So now you have 6 and 2/3+n=4. Well, 6 and 2/3+-(2+2/3)=4, so n=-(2+2/3).

[input]2/3+n+6=4[/input]