Aright triangle with hypotenuse 5 units and one leg 4 units is dilated with a scale factor of 2. what is the length of the smallest side of the new triangle

Ineed to know the answer to this algebra question.

Pepe and leo deposits money into their savings account at the end of the month the table shows the account balances. if there pattern of savings continue and neither earns interest nor withdraw any of the money , how will the balance compare after a very long time ?

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