What is your fav color?!
Mine is red and black :)

green

Step-by-step explanation:  Green is perceived as brighter because the human eye evolved to see it with greater sensitivity. Our receptors are tuned to it biochemically. ... the efficiency of the eye (or relative sensitivity of the human eye) is a function of the wavelength observed (lambda)

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: