Just did this one.
The perimeter is the sum of the sides.
n + (3n - 4) + (3n - 5) = 33
7n - 9 = 33
7n = 42
n = 6
3n-4=18-4=14
3n-5=13
Check: 6+14+13=33, good
Answer: 6 cm, 14 cm, 13 cm
Answer:
9 is the correct answer
(2×2+1)=5÷5×9=9