Question 814569
  <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
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
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Question states***Its area is 56 square centimeters.
  A = {{{(3x-13)*x = 56 cm^2}}}
Solving for x
  3x^2 - 13x - 56 =0
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}
{{{x = (13 +- sqrt( 841 ))/(6) }}}  
{{{x = (13 +- 29)/(6) }}}  
  x = 7   0r  x = -16/6 (tossing out negative solution for unit measure)
Width is 7cm  and length is 8cm   (3x-13)