Find the absolute maximum and absolute minimum of the function f(x,y)=3+xy-x-2y on the closed triangle with vertices (1,0),(5,0),(1,4)

Absolute max: _____________

attainted at ( _________ , ___________) , ( ____________ , _____________)

Absolute min: _____________

attained at ( __________ , ____________ ) , ( __________ , ____________ ) , ( __________ , ____________ )

Absolute max: _____________

attainted at ( _________ , ___________) , ( ____________ , _____________)

Absolute min: _____________

attained at ( __________ , ____________ ) , ( __________ , ____________ ) , ( __________ , ____________ )