SOLUTION: The question is: create a rectangle that has an area of 45 square centimetres and a peritimer of 36 centimetres. I have tried lots of numbers and it doesn't work.

Algebra ->  Surface-area -> SOLUTION: The question is: create a rectangle that has an area of 45 square centimetres and a peritimer of 36 centimetres. I have tried lots of numbers and it doesn't work.       Log On


   

Question 817225: The question is: create a rectangle that has an area of 45 square centimetres and a peritimer of 36 centimetres. I have tried lots of numbers and it doesn't work.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

create a rectangle that has an area of 45 square cm and a perimeter of 36 cm.



A+=+lw+=+45cm%5E2  0r l = 45/w

P+=+2%2845%2Fw%29+%2B+2w+=+36cm   |Multiplying thru by w so as all denominators = 1

   90 + 2w^2 = 36w

   w^2 - 18w + 45 = 0 

  (w-15)(w-3) = 0

  (w-15) = 0 , w = 15cm ,  l = 3cm

0r(w-3) = 0 ,  w = 3cm  ,  l = 15cm

Dimensions of the Rectangle are 3cm  by 15cm

 A = 45cm^2  and Perimeter = 2%2A3cm+%2B+2%2A15cm+=+36cm