Q.7 Find the perimeter of the rectangle whose length is 40 cm and a diagonal is 41 cm.

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