Length of rectangle = 40cm Diagonal = 41 cm \(Breath^2 = 41^2 - 40^2 \) Or, \( breath^2= 1681 – 1600 \) Or, breath = \(\sqrt{81} \) cm Breath = 9 cm Perimeter of rectangle = 2×(40+9) = 2×49 = 98 cm