Can someone explain this step by step so i can go over it on flipgrid ? i’ll give a brainlist

Can someone me with this problem . show your work .

What is the first step of an indirect proof of a number that is divisible by two

Mary beth used the mapping rule to find the coordinates of a point that had been rotated 90° counterclockwise around the origin. examine the steps to determine whether she made an error. m (3, –6) is rotated 90° counterclockwise. (x, y) → (–y, x) 1. switch the x- and y-coordinates: (6, –3) 2. multiply the new x-coordinate by –1: (6(–1), –3) 3. simplify: (–6, –3) .