Question 12

evaluate

-12.8

Step-by-step explanation:

Replace the letters with the respective values ( a = 4, b = 2, c = 3).

So (-3a+4b)^3 would become (-3 (4) + 4 (2))^3 = (-12 + 8)^3 = -4^3 = -64

And the bottom part (2c -1) would become (2 (3) - 1) = 6-1 = 5

So the final result would be -64 / 5 which is approximately -12,8

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: