y=-x+1
1) Since this line must bisect ∠LKJ then we can locate two points that belong to the line that divides equally ∠LKJ like point (3,-2) and (2,-1).
2) We can now proceed with that to find the slope of that line:

3) With the slope and one point we can find the linear coefficient plugging into the slope-intercept formula:
Plugging point (3,-2) and slope m=-1 we have:
y=mx + b
-2=3(-1)+b
-2=-3+b
-2+3 =b
b=1
Hence the the equation written in the slope-intercept formula is:
y=-x+1