Is y = 1/sqrt(x) a function? If so, what type of function it is?

How about y = | 1 - x^2 | ?

If you double the input of a function and it results in half the output, and if you triple the input and it results in a third of the output, what can be guessed about the function? check all that apply.

How many ordered pairs of positive integers satisfy xy=32?

3x = 729 solve for x plz . it's urgent. will mark