Given that \(-3 \le 7x + 2y \le 3 \) and \(-4 \le y - x \le 4\), what is the maximum possible value of \(x + y\)?

If you could explain this it would be AMAZING! Thank you so much!

HelpPLZ Oct 18, 2018

#1**+1 **

There may be an algebraic way to do this.....but I think it can be done graphically like this :

https://www.desmos.com/calculator/4fhytbda6x

It can be shown that some corner point [ a point in the feasible region of all the graphs] will maximize x + y [ the objective function]

Therea are two corner points here (-5/9, 31/9) and (5/9 , -31/9 )

Testing both points in the objective function,the corner point (-5/9, 31/9) will maxmize x + y =

-5/9 + 31/9 =

26/9

[ This is known as linear programming ]

CPhill Oct 18, 2018