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2003 Forester XS
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Discussion Starter #1
I am doing a half college half high school thing this year and i have math 141. Every other week my teacher gives us a homework with 4 or 5 multistep problems, all of which are very difficult. I am going to post the harder ones in here that i can't get. I would love any help you guys could give.
 

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2003 Forester XS
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Discussion Starter #2
Here is the first problem i have.
1.
A plot of land is going to be surrounded on all 4 sides. 3 sides will be made of wood and cost $5.75 a lineal foot. The fourth side will be made of stone and cost $11.75 a linear foot. Don't pay attention to thickness. What length and width will provide the most area for $1300?
 

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2007 XT Sport 5MT
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Here is the first problem i have.
1.
A plot of land is going to be surrounded on all 4 sides. 3 sides will be made of wood and cost $5.75 a lineal foot. The fourth side will be made of stone and cost $11.75 a linear foot. Don't pay attention to thickness. What length and width will provide the most area for $1300?
2W($5.75)+L($5.75+$11.75)=$1300

W = [1300-L(17.50)]/11.50

L = [1300-W(11.50)]/17.50

solve from there... i might've mucked up something, dont have a calculator handy
 

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2003 Forester XS
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Discussion Starter #9
Duderotomy has the idea. The answer is W=37.34...,L=56.21...,A=18,369.565. I also totally hate math but im good at it so i need to take it. And i want to get a MBA and a Doctorate in science so i need to just get used to it.
 

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Duderotomy has the idea. The answer is W=37.34...,L=56.21...,A=18,369.565. I also totally hate math but im good at it so i need to take it. And i want to get a MBA and a Doctorate in science so i need to just get used to it.
your A is a bit off there, might want to use a calc
 

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Duderotomy has the idea. The answer is W=37.34...,L=56.21...,A=18,369.565. I also totally hate math but im good at it so i need to take it. And i want to get a MBA and a Doctorate in science so i need to just get used to it.
So I was trying to complete duderotomy's math and it wasn't gong anywhere, how do you actually get those figures? Its amazing how fast you forget all this!:crazy:
 

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2009 Outback XT-B 5MT
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2W($5.75)+L($5.75+$11.75)=$1300

W = [1300-L(17.50)]/11.50

L = [1300-W(11.50)]/17.50

solve from there... i might've mucked up something, dont have a calculator handy
I think you did muck something up.

You have one equation with two unknowns. Your decomposition doesn't work either. You could rewrite your first equation as:

1300=17.5L+11.5W

Put L in terms of W, like you did, and you have L=(1300-11.5W)/17.5

Plug that into the initial equation, to give you a function of only W, and you'll see what happens...

1300=17.5((1300-11.5W)/17.5)+11.5W

The 17.5's cancel, leaving you with 1300=1300-11.5W+11.5W, so 0=-11.5W+11.5W

That is valid for W= any real number. W could equal 1,000,000,000, and you'd have -11,500,000,000+11,500,000,000=... Zero. All you really found out is that W=W, and I don't think that was the point.

To the OP, none of us are going to do your homework for you. If that is what you want, then I'd suggest posting somewhere else.

What we WILL do, is help point you in the right direction. The only way we can do that is if you tell us the steps you've taken, where you are stuck, and how you think the problem should work out. If you REALLY have no idea how to approach the problem, consider the work you are doing in class and apply that knowledge. We can't help you if you don't put forth the effort to try.

At the end of the day, the homework and all tests are up to you.
 

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2007 XT Sport 5MT
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^Yeah, when I got to the office and then actually looked at what I wrote I could see I botched it slightly. When you factor mine through I ended up with W=0 though and that wasn't quite right :lol:

I then gave up since I did my own homework back in school, and didn't have people on forums help me. Though I did have other friends help point me in the right direction when I'd get stuck.
Good luck though...
 

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08 XT Limited
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Actually, you are assuming that the shape must be a rectangle....

IF not, I can come up with 3 sides wood, 1 side stone (make it a "triangle-like" shape) final solution = 2150.79 square feet versus your 2098 and change.

I used 1 ft of stone on one side, and had $1288.25 to buy 224' of wood to for the other three sides. Of course, nobody said one side needed to be at least 1' long either. ;)

Sorry, I like puzzles and word problems....mix that in with a little bit of smart ***...
 
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