Let's deal with each factor in the numerator individually first: when evaluating the power of a power, you have to multiply the exponents: 
So, we have
^{-\frac{1}{2}} = 3^{2\cdot(-\frac{1}{2})} = 3^{-1},\quad (9^4)^{-1} = 9^{-4}](https://tex.z-dn.net/?f=%20%5Btex%5D%283%5E2%29%5E%7B-%5Cfrac%7B1%7D%7B2%7D%7D%20%3D%203%5E%7B2%5Ccdot%28-%5Cfrac%7B1%7D%7B2%7D%29%7D%20%3D%203%5E%7B-1%7D%2C%5Cquad%20%289%5E4%29%5E%7B-1%7D%20%3D%209%5E%7B-4%7D)
Now remember that
and
to rewrite the expression as

Now use the rules

to conclude

[3x] + [6x-2] + [x+3] + [4x+1] + [5x-2] = Perimeter
ANSWER.
19x
Multiply the divisor by as many 10's as necessary until we get a whole number. Remember to multiply the dividend by the same number of 10's
Square root 27 is 3squer root 3 so the answer is 2 square root three