I dont know which one it is helppo

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) .

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?

Given sin28.4=.4756, cos28.4=.8796, and tan28.4=.5407 find the cos of 61.6