Why is the function y = cosx a even function?

Do not comment if you aren’t going to . create a real-life situation and create a system and show how it might be modeled algebraically with a system of equations (or inequalities) show all work include a few sentences explaining the situation, your variables of choice and what each represents, and how you would set it up and solve it algebraically. !

Complete the solution of the equation. find the value of y when x equals to 1 9x-5y=29

Amachine part consists of a half sphere and a cylinder, as shown in the figure. the total volume of the part is π cubic inches.