Answer:
set two equation of line y=ax+b and y=cx+d
when these two lines are perpendicular to each other, then a*c=(-1)
set answer is y=ax+b
we can know that a=1/6
bring in a=1/6 and(-4,5)
5=(1/6)*(-4)+b
=>5=(-2/3)=b
=>b=5 2/3
answer is y=(1/6)x+5 2/3