Find the square roots of the following numbers. Give the steps correctly. \sqrt {19.9 }

Please give me the answer .

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

Select the correct answer from each drop-down menu. the length of a rectangle is 5 inches more than its width. the area of the rectangle is 50 square inches. the quadratic equation that represents this situation is the length of the rectangle is inches.

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.