Root 3-1/root3+1 simplify​

Assume cd | ab are parallel. find m2. a) x= 50° (b) x = 70° c) x = 30° d) x = 60

Which expression can be used to determine the slope of the line that passes through the points -6, three and one, -9

Which of the expressions (on the photo document i inserted) together represent all solutions to the following equation? 8cos(12x)+4=-4 *the answer should be in degrees.* > i would like for someone to explain the process to find the solutions for this.