The slope of a line of best fit is undefined when _____.
select all that apply

(1) the x values of the data set are constant
(2) the y values of the data set do not change when the x values change
(3) the slope of the line of best fit is vertical
(4) the slope is of the line of best fit is horizontal.
(5) the x values of the data set increase at an unspecified rate as the y values decrease