Let the width be "x" cm.
Then the length is "x+12" cm
And the area = x(x+12) = x^2+12x cm^2
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Change the dimensions:
width = "x-2" cm
length = "x+10" cm
New area = (x-2)(x+10) = x^2 + 8x - 20 cm^2
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Equations :
Old area - New area = 108 cm^2
x^2+12x -(x^2 + 8x - 20) = 108
4x + 20 = 108
4x = 88
x = 22 cm (original width)
x+12 = 24 cm (original length)
