Help me pls i need an answer quick

8 * 7(21/3)

Why is it difficult to find length of the hypotenuse the same way the length of the legs can be found?

Find and simplify an expression for the area of five rows of x squares with side lengths of x centimeters .

You have $600,000 saved for retirement. your account earns 5.5% interest. how much, to the nearest dollar, will you be able to pull out each month, if you want to be able to take withdrawals for 20 years?