What is the length of the side of a right triangle that has a hypotenuse that is 15 mm and a side of 9 mm

1foot = 12 inches; 1 yard = 3 feet

Math it's appreciated. (picture provided)

Ms.ortiz sells tomatoes wholesale. the function p(x)=-80x^2+320x-10, graphed below, indicates how much profit she makes on a load of tomatoes if she makes on a load of tomatoes if she sells them for 4-x dollars per kilogram. what should ms.ortiz charge per kilogram of tomatoes to make on a load of tomatoes?