Find the minimum value of f(x,y)=y-x+1 for the polygonal convex set determined by this system of inequalities. X or = 0 Y or =0 2x+Y

Question

Find the minimum value of f(x,y)=y-x+1 for the polygonal convex set determined by this system of inequalities. 

X> or = 0    Y> or =0    2x+Y< or =4

monkey* · Answer

Any help?

irishboy123 · Answer

$f(0,0) = 1$
$ f(x,y)=y-x+1$
$f_x = -1, \, f_y = 1$

so $f_{min}  = f(2,0) = -1$

monkey* · Answer

Would that be my answer? @IrishBoy123

irishboy123 · Answer

that would be my answer, and if it is wrong, i could justify my approach

it is not clear to me how "you" are supposed to approach this, eg what are you learning right now.  i just blagged it using some general knowledge

if you want more help i can tag some poeple

monkey* · Answer

Yes, please. I'm completely lost on this problem.

irishboy123 · Answer

before i do so, what are you learning now?  that might provide a clue as to how you are expected to approach/solve it

monkey* · Answer

Would your answer be (2,0) or -1? Because if it's the (2,0), that would make more sense to me. But I'm learning system of linear equations and inequalities. Matrices also.

irishboy123 · Answer

it is 2,0

i have looked on line and you are supposed to plot the region and then just plug in values for x and y.  that kinda is what the calculus shortens

so

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irishboy123 · Answer

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