PLEASE HELP!!

The line with equation y = mx + b is perpendicular to the line with equation y = 16 - x/3.  The value of m is?

a) -3

b) -1/4

c) 3

d) -1/3

e) 1/3

Hello SmartMathMan!

$y=16-x/3$

$is\ identical\ to \\ y=-\frac{1}{3}x+16$

$m=-\frac{1}{(-\frac{1}{3})}$

$m=3$

  !