What is the value of r? 3/5 (r - 7) = 1

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

Alake near the arctic circle is covered by a 222-meter-thick sheet of ice during the cold winter months. when spring arrives, the warm air gradually melts the ice, causing its thickness to decrease at a constant rate. after 333 weeks, the sheet is only 1.251.251, point, 25 meters thick. let s(t)s(t)s, left parenthesis, t, right parenthesis denote the ice sheet's thickness sss (measured in meters) as a function of time ttt (measured in weeks).

What are the sotions to the quadratic equation 9x^2=4