Suppose that y is inversely proportional to the 4th power of x, and that y=15 when x=5. What is y when x=7? Round your answer to two decimal places if necessary.

y = 3.91 when x =7

Step-by-step explanation:

y = k / x⁴

Where,

k = constant of proportionality

y=15 when x=5

y = k / x⁴

15 = k / 5⁴

Cross product

15 × 5⁴ = k

15 × 625 = k

9,375 = k

What is y when x=7?

y = k / x⁴

= 9,375 / 7⁴

= 9,375 / 2401

= 3.9046230737192

Approximately

y = 3.91

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:

1,150 give brainliest

step-by-step explanation

2r= 2300

r =1150