7.) The temperature at 7:00am in Madison, Wisconsin was -3.5°F. By 1:00pm the temperature had risen by 11.3°F. Choose the equation that shows the temperature, in degrees Fahrenheit, at 1:00pm.
1 point
-3.5 + 11.3 = 14.8
-3.5 - 11.3 = -14.8
-3.5 + 11.3 = 7.8
-3.5 - 11.3 = 7.8

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: