1. ## Word

I am having trouble with a word problem. I know I have to set up the minimizing function then i can state the domain then find the minimum dimensions as well. I just confuse overall so please help.

7) A page is to contain 30 square inches of print. The margins at the top and the bottom of the page are each 2 inches wide. The margins on each side are only 1 inch wide. Find the dimesions of the page so that the least paper is used.

2. Originally Posted by uniquereason81
I am having trouble with a word problem. I know I have to set up the minimizing function then i can state the domain then find the minimum dimensions as well. I just confuse overall so please help.

7) A page is to contain 30 square inches of print. The margins at the top and the bottom of the page are each 2 inches wide. The margins on each side are only 1 inch wide. Find the dimesions of the page so that the least paper is used.
let the area of print be $xy=30$...then you have to set up the area of the page be $A=(x+2)(y+1)$

go from there

3. how did you get that equation

4. Hello,

Suppose that the printed part is a rectangle of sides x and y (x will be the length, y the height). And assuming that the paper is rectangular..
The area of the printed part is $xy=30$

Since there is a margin on top and on bottom of 2 inches each, the height of the paper will be $y+4$

And since there are two lateral margins of 1 inch each, the length of the paper will be $x+2$

Hence the area of the paper will be $A=(x+2)(y+4)$

So find x and y such as A is minimized, and remember that $xy=30$

Hence I'd advise you to develop the expression for A

5. Originally Posted by Moo
Hello,

Suppose that the printed part is a rectangle of sides x and y (x will be the length, y the height). And assuming that the paper is rectangular..
The area of the printed part is $xy=30$

Since there is a margin on top and on bottom of 2 inches each, the height of the paper will be $y+4$

And since there are two lateral margins of 1 inch each, the length of the paper will be $x+2$

Hence the area of the paper will be $A=(x+2)(y+4)$

So find x and y such as A is minimized, and remember that $xy=30$

Hence I'd advise you to develop the expression for A
I always forget the double margin thign....grumbles

6. Attention is part of success

7. Originally Posted by Moo
Attention is part of success
That is why I will never succeed

8. I am so sorry Moo and Mathstud but I am still lost

9. Try to understand with this sketch

(I'm sorry, but I've made it with Paint )

10. Wow something hard can become easy with a simple diagram. THANKS

11. Glad to see you understood the thing