Question

the length of a rectangle is tree times its width and the length of its digonal is 6 root 10cm the perimeter of the rectangle is

Answer 1

let length be 3x
breadth be x
by Pythagoras theorem
(3x)^2+x^2=(6√10)^2
√9x^2+x^2=6√10
√10x^2=6√10
√10 x= 6√10
x= 6
length of a rectangle is 18cm
breadth of a rectangle is 6cm
perimeter is 2(l+b)
= 2(18+6)
=2(24)
48 cm
therefore perimeter of rectangle is 48cm