Can some help me calculate the value of x?

If cos(2x) = tan^2(y), show that cos(2y) = tan^2(x).

Matt had 5 library books. he checked out 1 additional book every week without retuening any books. whats the matching equation

Jack is considering a list of features and fees for current bank: jack plans on using network atms about 4 times per month. what would be jack’s total estimated annual fees for a checking account with direct paycheck deposit, one overdraft per year, and no 2nd copies of statements? a. $44 b. $104 c. $144 d. $176