Rectangle: x=0,y=0,x=3,y=4, area =12. Center =(3/2,2).
Slope of 3x+y+6=0 is −3, so slope of L=1/3.
A line through the center of a rectangle bisects its area. So L passes through (3/2,2) with slope 1/3:
y−2=31(x−3/2)
⇒x−3y+29=0
⇒2x−6y+9=0.
Distance from (1/2,−5):
d=4+36∣2(1/2)−6(−5)+9∣
=40∣1+30+9∣=21040=210.