The rule (x,y)→(y,−x) takes a line to a perpendicular line. Select all the rules that take a line to a perpendicular line.

Answer 1

major rule to get to a perpendicular line is

the slope is the negative inverse

if y=2x is the initial line which has slope =2

then the perpendicular line is: y=(-1/2)x = -x/2 which has slope =-1/2

-1/2 is the negative inverse of 2

if you're using polar coordinates

(r,theta) goes to (r,theta+90) or (r, theta+pi/2)

rotate the line 90 degrees

as perpendicular lines are at right angles with the original lines