What is the slope of a line that is perpendicular to the line y=-1/3x-6?

Y=-1/3x-6, for this line, the slope (m) is - 1/3.

This is because the equation is in the slope intercept form: y = mx + b.

The perpendicular line to one with m = - 1/3, is the negative reciprocal of m, we'll call it m2.

m2 = - - 3/1 = + 3/1 = 3