Solve the whole thing. 2 different ways to solve it and it has to be able to use the formula in different problems as well

There are 15 plates and each plate is either 7 or 12 inches diameter. which systems of equations do you use to find the number of 7 inch plates, x and 12 inch plates, y

Which of the following values cannot be probabilities? 0.08, 5 divided by 3, startroot 2 endroot, negative 0.59, 1, 0, 1.44, 3 divided by 5 select all the values that cannot be probabilities. a. five thirds b. 1.44 c. 1 d. startroot 2 endroot e. three fifths f. 0.08 g. 0 h. negative 0.59

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.