The area of a rectangle is 27 square meters. If the length is 6 meters less than 3 times the width, then find the dimensions of the rectangle. Round off your answers to the nearest hundredth.

Respuesta :

Length (L): 3w - 6

width (w): w

Area (A) = L x w

        27 = (3w - 6)w

        27 = 3w² - 6w

          0 = 3w² - 6w - 27

          0 = 3(w² - 2w - 9)

 w = [tex][-(-2) +/- \sqrt{(-2)^{2}  - 4(1)(-9) }]/2(1)[/tex]

    =  [tex][2 +/- \sqrt{(4  + 36 }]/2[/tex]        

   = [tex][2 +/- \sqrt{(40 }]/2[/tex]  

   = [tex][2 +/- 2\sqrt{(10 }]/2[/tex]  

   =  [tex][1 +/- \sqrt{(10 }][/tex]

since width cannot be negative, disregard 1 - √10

w = 1 + √10  = 4.16

Length (L): 3w - 6   = 3(4.16) - 6   = 12.48 - 6   = 6.48

Answer: width=4.16 meters, length=6.48 meters