Convert 99% to a decimal

In the 30-60-90 triangle below side s has a length of and side r has a length

One of the same side angles of two parallel lines is 20° smaller than the other one. find the measures of these two angles.

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.