## JianEnriquez one year ago Kindly help me review with maxima and minima problems with this question

1. JianEnriquez

A rectangular page is to contain 138 square inches of printable area. The margins at the top and bottom of the page are each 1 inch, one side margin is 1 inch, and the other side margin is 2 inches. What should the dimensions of the page be so that the least amount of paper is used?

2. Loser66

|dw:1435156728524:dw|

3. Loser66

|dw:1435156834748:dw|

4. Loser66

by replacing a = 138/b to (a+4)(b+2) to get something, then take derivative and let it =0 to solve for b.

5. JianEnriquez

ohhh, i get it, slr, my internet is slow

6. Loser66

ok

7. JianEnriquez

i can simplify (a+4)(b+2) first before i substitute right? and then take the derivative of that equation?

8. Loser66

yes

9. JianEnriquez

so my y prime is 4-276b^-2

10. JianEnriquez

my answers are $a=2\sqrt{69}, b=\sqrt{69}$

11. JianEnriquez

thanks again !