Solve for x and y: 7y−5x=31 & x=4−2y

Solve the x in the equation x^2+14x+17=-96

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.

Is the power produced directly proportional to the wind speed, give reasons for your answer?