Question 111369
First find the slope through (0, 5) and (-3, -4) 


*[invoke slope 0, 5,-3, -4]


So the slope is also {{{m=3/1}}}. Now any perpendicular slope is simply the negative reciprocal of {{{m=3/1}}}. So negate {{{3/1}}} to get {{{-3/1}}}. Now flip  {{{-3/1}}} to get {{{-1/3}}}



So any perpendicular slope is {{{m=-1/3}}}