Please help me with the 2 last ones!,Thank you so much!!(if you atleast helped or tried)

The border line of the linear inequality 4x + 7y < 5 is dotted true or false?

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.

Solve the following pair of equations for x and y: ax/b_ by /a= a +b; ax - by = 2ab