SOLUTION: The length of a rectangle is 13 centimeters less than three times its width. Its area is 56 square centimeters. Find the dimensions of the rectangle

Algebra ->  Rectangles -> SOLUTION: The length of a rectangle is 13 centimeters less than three times its width. Its area is 56 square centimeters. Find the dimensions of the rectangle      Log On


   

Question 814569: The length of a rectangle is 13 centimeters less than three times its width. Its area is 56 square centimeters. Find the dimensions of the rectangle
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

The length of a rectangle is 13 centimeters less than three times its width.

Let x represent the width and (3x-13) the length



Question states***Its area is 56 square centimeters.

  A = %283x-13%29%2Ax+=+56+cm%5E2

Solving for x

  3x^2 - 13x - 56 =0

x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%2813+%2B-+sqrt%28+841+%29%29%2F%286%29+  

x+=+%2813+%2B-+29%29%2F%286%29+  

  x = 7   0r  x = -16/6 (tossing out negative solution for unit measure)

Width is 7cm  and length is 8cm   (3x-13)