geometry
posted by jay .
The width of a rectangle is 6 cm less than its length. If the area of the rectangle is 135 square cm, find the dimensions. Then find the perimeter of the rectangle.

W = Width
L = Length
A = Area
W = L  6
A = W * L
135 =( L  6 ) * L
135 = L ^ 2  6 L
The exact solution are :
L =  9 cm
and
L = 15 cm
The length can't be negative so:
L = 15 cm
W = L  6
W = 15  6 = 9 cm
A = W * L = 15 * 9 = 135 cm ^ 2
P. S.
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135 = L ^ 2  6 L
Go on:
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When page be open in rectangle type:
solve 135 = L ^ 2  6 L
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After few seconds when you see result click option:
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perimeter of a rectangle with length 6.6m and width 4.5