Y=41 is a zero slope line, so any line that is also zero sloped will satisfy for parallel lines....for example Y=3, y=0, y = -8....
For perpendicular they need to have the negative multiplicative inverse of the first line....in this case 0. So then we have to apply the vertical lines to make them perpendicular....so X = 41 or x = 2 or x= -9 would all be perpendicular.
Summed up zero slope gives horizontal lines and equations of y = any number. Undefined slopes give you vertical slopes and result in equations x = any number.
