5^x-3^x=16 then find x

Ineed ! the person who answers and shows their work on they got the answer first will be marked the !

Dakota earned $7.50 in interest in account a and $18.75 in interest in account b after 15 months. if the simple interest rate is 4% for account a and 5% for account b, which account has the greater principal? explain. to make it a little easier, there is an image. good luck!

What is another way to express 36 +32