Solve for
x. Round to the nearest tenth of a degree, if necessary.

Step-by-step explanation:

Note that the figure is a right triangle, and that we are given the length of the side adjacent to x and the hypotenuse of the triangle.

Therefore, we can use the cosine ratio. Recall that:

The adjacent side is 8.5 and the hypotenuse is 9.9. Therefore:

We can take the inverse cosine of both sides:

Use a calculator. Hence:

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:

c. (3,2,6) is the answer.