Question 146723
First you need to find the line that is perpendicular to {{{5x-12y+33=0}}} (it will also be perpendicular to {{{5x-12y-6=0}}})



Now this line will intersect with both equations 5x-12y+33=0 and 5x-12y-6=0. So you want to find the points of intersection. From there, simply use the distance formula {{{d=sqrt((x[2]-x[1])^2+(y[2]-y[1])^2)}}} to find the distance between the two points of intersection. I hope that's enough to get you started.