Just did a specific one of these; let's do the general case.
The point nearest the origin is (a,b).
The line from the origin through the point is
The line we seek is perpendicular to this one. We swap the coefficients on x and y, negating one, to get the perpendicular family of lines. We set the constant by plugging in the point (a,b):
That's standard form; let's plug in the numbers: