What is the slope of the line that goes through the points (12, 5) and (7, 2)

Given that de, df, and ef are midsegments of △abc, and de=3.2 feet, ef=4 feet, and df=2.4 feet, the perimeter of △abc is .

The depth of a lake at a certain point, wich is a function of the distance of that point from shore, is 30 feet.

What is the definition of exponential decay?