Bradley is returning home from a place that is 2 kilometers away. the function y = 2,000 − 90x represents bradley's distance from home in meters, y, in relation to the number of minutes he walks, x. which statements about this function are true?

In an algebraic equation, you should have at least 2 variables: the independent and the dependent. The independent variable in this case, is the parameter that cannot be controlled - time. This is expressed in minutes using the variable x. The dependent variable is the parameter you want to measure - the distance expressed using the variable y. Since the problem states a parameter of distance in terms of 2 kilometers, y=2. Therefore, I think the choices would be about the amount of minutes it would take for Bradley to cover this distance. Assuming this is the case, then the answer would be:
 
2 = 2000 - 90x
90x = 2000-2
90x = 1998
x = 1998/90
x = 22.3 minutes
 
It would take 22.3 minutes for Bradley to cover the 2 kilometers so that he could get home.