Question 227552
Thru (6,-4)and perpendicular to 3x-y-5=0
-y=-3x+5 
y=3x-5 This line has a slope=3. (red line)
The perpendicular line will have a slope=-1/3.
-4=-1/3*6+b
-4=-6/3+b
b=-4+6/3
b=-4+2
b=-2 The y intercept.
y=-x/3-2 equation for the perpendicular line thru (6,-4). (green line)
{{{ graph( 300, 300, -6, 6, -6, 6, 3x -5, -x/3 -2) }}} (graph 300x300 pixels, x from -6 to 6, y from -6 to 6, of TWO functions 3x -5 and -x/3 -2).