For each planet in a solar system, its year is the time it takes the planet to revolve around the center star. The function f (x )equals 0.2 x Superscript 3 divided by 2 models the number of Earth days in a planet's year, f(x), where x is the average distance of the planet from the center star, in millions of kilometers. There are approximately 365 Earth days in the year of Planet Upper C. What is the average distance of Planet Upper C from the center star?

incomplete question. how do you expect anyone to you when you do not post the question in its entirety?

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:

ab will be equal to