Suppose f(x,y)=xy(1−10x−4y).
f(x,y)f(x,y) has 4 critical points. List them in increasing lexographic order. By that we mean that (x, y) comes before (z, w) if x
First point (____________,__________)
Classification:

Second point(__________,__________)
Classification:

Third point (___________,_________)
Classification:

Fourth point (__________,_________)
Classification: