Question

What is the equation of a line that is perpendicular to the line represented by y = 3/4 x - 1/2?

Answer 1

The slope of the given line is the x-coefficient, 3/4. The slope of a perpendicular line will be the negative reciprocal of that, -1/(3/4) = -4/3.

A line with a y-intercept of zero will do.
.. y = (-4/3)x