Gas mileage is the number of miles you can drive on a a gallon of gasoline.
a test of a new car results in 360 miles on 20 gallons of gas. how far could
you drive on 70 gallons of gas? what is the car's gas mileage?

the cars gas mileage is 18 miles per gallon, which on 70 gallons would result in 1260 miles

Step-by-step explanation:

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: