Investigating Trace and Level Curves

Consider the function f(x,y) =

. Slide x to see the trace at y = 2. Spin the graph to view around. Now what is the value of y such that the trace hit the tallest points on the graph? What is the value of y such that the trace hit the lowest points on the graph? Next, uncheck Trace and check Level Curves. Then slide k to see the level curves