Question 227095
The length of a rectangle is 9 inches more than the width. Its area is 112 square inches. Find the dimensions of the rectangle.


Step 1.  The area A of a rectangle is given as A=length*width.


Step 2.  Let w be the width.


Step 3.  Let w+9 be the length


Step 4.  Then, A=w(w+9)=112 or w^2+9w-112=0


Step 5.  To solve, use the quadratic formula given as


{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}


where a=1, b=9, and c=-112


*[invoke quadratic "w", 1, 9, -112 ]


For w=7 , then w+9=16 and A=7*16=112 which is a true statement.


Step 6.  ANSWER:  The width is 7 inches and the length is 9 inches.


I hope the above steps were helpful. 


For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.


And good luck in your studies!


Respectfully,
Dr J


drjctu@gmail.com


http://www.FreedomUniversity.TV
http://www.Facebook.com/FreedomUniversity.TV
http://www.Twitter.com/FreedomUTV