Let F(x, Y) = $x ^ { 2 }$ - Xy

Multiple Choice

Let f(x, y) = $x ^ { 2 }$ - xy + $y ^ { 2 }$ + 2y - 4. The point $- \frac { 2 } { 3 } , - \frac { 4 } { 3 }$ is a

A) relative maximum
B) not a relative extreme point
C) absolute maximum
D) relative minimum