Need help with this please I can’t seem to find the correct answer choice

Marco has $38.43 dollars in his checking account. his checking account is linked to his amazon music account so he can buy music. the songs he purchases cost $1.29. part 1: write an expression to describe the amount of money in his checking account in relationship to the number of songs he purchases. part 2: describe what the variable represents in this situation.

Select the sequences that are geometric.

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