What does this expression represent

Select the quadratic that has root x = 8 and x = -5

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10

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.