SOLUTION: Hello, I need help with problem: The length of a is 4 centimeters more than the width. If the length is increased by 8 centimeters and the width is decreased by 4 centimet

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Question 90935: Hello,
I need help with problem:

The length of a is 4 centimeters more than the width. If the length is increased by 8 centimeters and the width is decreased by 4 centimeters, the area will remain unchanged. Find the orignal demensions of the rectangle.

Thank you

Answer by malakumar_kos@yahoo.com(315) About Me  (Show Source):
You can put this solution on YOUR website!

The length of a is 4 centimeters more than the width. If the length is increased by 8 centimeters and the width is decreased by 4 centimeters, the area will remain unchanged. Find the orignal demensions of the rectangle



Let the width of the rectangle be = x
Then the length of the rectangle = x+4 cm
Therefore the Area of the rectangle A = x.(x+4) sq cms
Altered length of the rectangle = x+4+8 = x+12 cms
Altered width of the rectangle = x-4 cms
Area of the rectangle = A = (x-4).(x+12) sq cms
The Areas remain unaltered
x.(x+4) = (x-4).(x+12)
x^2+4x = x^2-4x+12x-48
x^2-x^2+4x+4x-12x+48 = 0
-12x+8x+48 = 0
48 = 4x
x = 48/4 = 12

The original width = 12 cms
The original length = 12+4 = 16 cms