Linear Programming 3: Graphical Solution – with negative coefficients

This video shows how to graphically solve a maximization LP model that has
1) constraints with negative coefficients
2) fractional plotting points

LP model Solved:
Max -3X + 12Y
s.t.
7X - 1Y ≤ 3
-3X + 6Y ≤ 10
3X + 4Y ≤ 9
3X + 3Y ≥ 3
X, Y ≥ 0

Linear Programming 1: Graphical Solution -Extreme/Corner Points

Linear Programming 2: Graphical Solution - Minimization

Linear Programming 4: Slack/Surplus, Binding Constraints, Standard Form

Linear Programming 5: Alternate solutions, Infeasibility, Unboundedness, & Redundancy

[katherinebalka]

You have a wonderful voice and your videos are so well made and good at explaining the solution! Thanks for the help!!!

[kathleenferguson]

Very clearly and thoroughly explained. You make it seem quite easy. Thank you.

[bisikoobee]

Thanks so much for very good explanation. You've helped me to prepare for a midterm. My God will continue to strengthen you and help you in all your endeavours.

[EldoNorte]

For finding the straight line axis values A and B, one can also transform their equation in the form (X/A) + (Y/B) = 1

[thajisajir]

Thank you Sir. You helped to solve my homework.

[sejvihasani]

I couldn't not thank you. so, thank you very very much

[programmingintellects]

you helped me in my exams ... soo thankful to u

[SanjayGupta-zfvc]

Thnk u so much for explanation in detail....

[mohammadhassan]

thanx too much ..I hope that you can also be described the simplex method...in the same charming and understanding way

[arifnoman]

well explained..thank you so much
sir explain simplex method. plz

[Nightsaberban]

Thanks I think I can do what I was stuck on now!

[ejirogift]

thanks a lot for this it has been really helpful... i just have a little challenge. i came across a question to formulate a linear programming problem with a maximization objective. let the model have 5 constraints with the first and third constraints having 7 unknowns. at least one of the constraints should be left with 3 unidentified resources combination, but the second and fifth constraints should have 5 resource mix each. please how do i go about this?

[itsdannyftw]

3:02: "are less than constraints and are satisfied in the direction of the origin".
Is it just a coincidence that this worked for the *negative* coefficient constraint -3X +6Y <= 10 (purple line)?

Because if you try it on this negative constraint: -3x + 2y ≤ -4
You'll realise that even though this is a "less than constraint", it will NOT be satisfied in the direction of the origin (as far as I know, unless I graphed it incorrectly), like you stated in the video.

Rather, it will be satisfied away from the origin... and the only way to have worked this out is to have input a test coordinate, like you had suggested in the comments earlier. Funnily you didn't do this when graphing the purple line, so was it just a coincidence that you got lucky to know which direction to shade in? Or how did you know exactly without inputting test coordinates?

[ibrahimsabthasildar]

Sir how we consider the constraints of 0 1 2 mutipication

[MrOcean]

thanx a lot you're the best
Regards

[matinajazmine]

Am getting opposite answers when I do it with u .I dunno why

[burgerkini]

i'm just confused where does the 0.5 came from

[cherdoudayoub]

Thanks sir
But I don’t understand
Min Z= -x - y
Sc -x + y =< 2
x+y = 4
x >= 0 ; y >= 0
Help me plz
Thanks