Question

The perimeter if a rectangle us 68cm.if its breadth is 4 cm less than its length, find the length and breadth.

Answer 1

Let the length and breadth of the rectangle are l cm and b cm. 
Then, b=l-4
perimeter of the rectangle=2(l+b)=68
or,2l+2(l-4)=68
or,4l-8=68
or,4l=68+8
or,l=76/4
or,l=19cm
then b=l-4=19-4=15cm

Answer 2

Length = x cm
Breadth = x - 4 cm
Perimeter = 68
2(l+b) = 68
(x+x-4) = 34
2x = 38
 x = 19
Length = 19 cm
Breadth = 15 cm