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Perimeter = 2(Length + Width)
or P = 2((2x - 5) + x) = 2(3x - 5)

Given: P = 50 in.
So 50 = 2(3x - 5)
or
or 25 = 3x - 5
or 3x = 25 + 5 = 30
or
or x = 10 in

Hence, Length = (2x - 5) = 2 x 10 - 5 = 20 - 5 = 15 in
and width = x = 10 in.

Thus the length and width are 15 in and 10 in respectively.