Answer:
1/3
Step-by-step explanation:
Perpendicular lines have a slope that is the opposite reciprocal of the original line slope. To find it, first flip the fraction (-3 to -1/3). Then, add/get rid of the negative sign based on if it was there in the first place (-1/3 to 1/3). Thus, the slope would be 1/3.
Hope this helped :)
