What is the value of a?

Show your workcan a right triangle have this sides? *how to prove it without using the pythagorean theorema*

The serenity and the mystic are sail boats. the serenity and the mystic start at the same point and travel away from each other in opposite directions. the serenity travels at 16 mph and the mystic travels at 19 mph. how far apart will they be in 3 hours?

To decrease an amount by 16% what single multiplier would you use