(2/3)^2 comes out to 4/9
We now have 6 - 4/9
You can make 6 a fraction by putting 1 as the denominator.
6/1 - 4/9
You need to change the first denominator so that it is equal to 9. Multiply 6/1 by 9/9 to get 54/9.
54/9 - 4/9 = 50/9
The answer is D) 50/9
Hope this helps =)