Really struggling, anyone mind explaining?

Step-by-step explanation:

You can solve this by splitting it into a net and calculating the areas of each shape

Count the triangles: 4

rectangles: 1

area of a triangle: 0.5 x b x h

area of a square : L x W

4(0.5 x b x h) + L x W = surface area

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation: