The points D(0,0) (E4,0) F(4,4) join to make the triangle DEF. What is the equation of the line that passes through these points?

E and F ---
D and E ---
F and D ---

At the beginning of year 1, carlos invests $600 at an annual compound interest rate of 4%. he makes no deposits to or withdrawals from the account. which explicit formula can be used to find the account's balance at the beginning of year 5? what is, the balance?