Please help!! Use a trig function in each problem to find x

If x = 12 and y = 3, what is the value of x - y 2? 81 6 3 18

When a rectangle is dilated, how do the perimeter and area of the rectangle change?

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.