9x+3y=36
3y=-9x+36
y=-3x+36
For lines to be perpendicular their slopes must be negative reciprocals of each other...mathematically:
m1*m2=-1 and in this case for a line to be perpendicular to y=-3x+36 that line must have a slope of:
-3m=-1, m=1/3 so
y=x/3+b, and using point (6,2) we can solve for b, the y-intercept...
2=6/3+b
2=3+b
b=-1 so the perpendicular line passing through the point (6,2) is:
y=x/3-1 or more neatly...
y=(x-3)/3