Saturday, July 19, 2014

Length exceeds width by 2 feet. When each dimension is increased by 2 feet the area increases by 48 square feet. Find the dimensions.

We'll put the width as
x.


We'll put the length as x +
2.


The area of the rectangle is theproduct of length and
width.


A = x(x+2) (1)


We'll
increase dimensions by 2 feet:


The length will become x + 2
+ 2 = x + 4


The width will become x +
2.


The area is increasing also by 48 sq.
feet.


48 + A = (x+2)(x+4)
(2)


We'll substitute A by
(1):


48 + x(x+2) =
(x+2)(x+4)


We'll move all terms in x to the left
side:


x(x+2) - (x+2)(x+4) + 48 =
0


x^2 + 2x - x^2 - 6x - 8 + 48 =
0


We'll combine and eliminate like
terms:


-4x + 40 = 0


-4x =
-40


x = 10


The
width is of 10 units and the length is of 12 units: l=12 units; w=10
units.

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