Why is the product of two rational numbers always rational? Select from the drop down menus to correctly complete the proof. The options are either integers or irrational numbers.

Let a/b and c/d represent two rational numbers. This means a, b, c, and d are ___ and ___. The product of the numbers is ac/bd, where bd is not 0. Because integers are not closed under , ac/bd is the ratio of two integers, making it a rational number.

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step-by-step explanation:

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1 and 2

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: