Answer:
Any ordered pairs which have a slope of 5/4.
Explanation:
The line has a slope of -4/5 which means the y values have a difference of -4 and the x values have a difference of 5. If the line is perpendicular to this line then its slope must be the negative reciprocal which is 5/4. Any points which have a difference in y values of 5 and a difference of x values of 4 will be on some line perpendicular to the original.