Please help... Find the coordinates of the intersection of the diagonals of parallelogram GHJK with vertices G(1,3), H (2,1), J(-1,-5), and K (-2, -3)

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.

Plot the points (0,6), (3,15.8), and (9.5,0) using the graphing tool, and find the function

Anyone know? will mark brainliest if correct