# Need some help please

• Jul 28th 2006, 01:01 AM
kwtolley
Need some help please
The minimum value of z=4x+10y subject to
3x+y<=to24
6x+4y<=to66
x>=to0,y>=to 0. is.

My answer after looking at a list of possible answers is 32, is this right.
a.165
b.110
c.44
d.32
Thanks for any help given.
• Jul 28th 2006, 04:13 AM
galactus
Yep, that's what I got.
• Jul 28th 2006, 02:07 PM
Soroban
Hello, kwtolley!

Am I reading it wrong?
Are there typos in the problem?

Quote:

The minimum value of $\displaystyle z \:=\:4x+10y$ subject to: $\displaystyle \begin{Bmatrix}3x+y\,\leq\,24 \\ 6x+4y\,\leq\,66 \\ x \geq 0\\ y \geq 0\end{Bmatrix}$ is:

$\displaystyle a)\;165\qquad b)\;110\qquad c)\;44\qquad d)\;32$

Doesn't $\displaystyle x = 0,\;y = 0$ satisfy the inequalties?

• Jul 28th 2006, 03:01 PM
galactus
By Jove, Soroban, I think you're right. Here's the graph.

http://img47.imageshack.us/img47/5595/lpiiuk9.jpg
• Jul 28th 2006, 03:13 PM
galactus
Soroban, I just ran this through the Linear Programming solver in Maple and it gave me (0,0) as the minimum. I looked right past the origin.

Looks like the list of answers is omitting the correct minimum. That's why you're the man and I'm just a dogface ;) .

Good 'ketch' :) .
• Jul 29th 2006, 01:20 AM
kwtolley
Thanks to you both
Thats what I thought it would be, 32. Thanks so much for checking my answer.
• Jul 29th 2006, 05:18 PM
ThePerfectHacker
galactus are you using the program I use? If you are, how you like it?
• Jul 29th 2006, 05:36 PM
galactus
I like it a lot. What's even better, it's free. It's that Padowan thing; I downloaded it. I sometimes have trouble getting it to shade what I want to shade, but other than that it's great. Is this what you have?.
• Jul 29th 2006, 06:04 PM
ThePerfectHacker
Quote:

Originally Posted by galactus
Is this what you have?.

Same one you have. Great thing it is free. Also safe, cuz many free programs are adware. Finally, do you know it can approximate a set a points with different curves?
• Jul 29th 2006, 07:19 PM
JakeD
Quote:

Originally Posted by kwtolley
The minimum value of z=4x+10y subject to
3x+y<=to24
6x+4y<=to66
x>=to0,y>=to 0. is.

My answer after looking at a list of possible answers is 32, is this right.
a.165
b.110
c.44
d.32
Thanks for any help given.

As Soroban noted, the minimum value is 0, not on the list. So there is a typo. From this linear programming solver, which you can use to both solve the problem or check your work, the maximum value is 165, answer a.

If you have linear programming problems to solve in the future, you may want to bookmark that solver.
• Jul 30th 2006, 01:50 AM
galactus
Quote:

Originally Posted by ThePerfectHacker
Same one you have. Great thing it is free. Also safe, cuz many free programs are adware. Finally, do you know it can approximate a set a points with different curves?

No, I haven't delved into that feature. It's very user friendly.