When you are finding a line that is perpendicular, you need to look at the slope. In the format, y=mx+b, the m represents the slope. In this case, the slope (m) of the line is -1/9. A line with a perpendicular slope is the negative inverse. The negative inverse for -1/9 is 9/1. Once you know the slope, you can begin to plug in the new information in order to find the new b (y intercept).
New Line information:
m=9/1, (2,-5) --> this means that x = 2 and y = -5
-5 = 9/1(2) + b
-5 = 18 + b
-23 = b
Once you find the b, you plug the b and m into the equation y = mx + b
y = 9/1x -23