The length of a rectangle is three times of its width. If the length of the diagonal is 8√10 then find the perimeter of the rectangle.	Select the correct option
A) 77 cm	B) 88 cm	C) 64 cm	D) 11 cm	E) 18 cm

Rationale: let breadth = x cm , then , length = 3 x cm x 2 + ( 3 x ) 2 = ( 810 − − √ ) 2 = > 10 x 2 = 640 = > x = 8 x 2 + ( 3 x ) 2 = ( 810 ) 2 = > 10 x 2 = 640 = > x = 8 so , length = 24 cm and breadth = 8 cm perimeter = 2 ( l + b ) = 2 ( 24 + 8 ) = 64 cm answer : c
Answer: C