Question 923878
Length = x
Breadth = x - 3
Perimeter = 2 times length + 2 times breadth
58 = 2(x) + 2(x - 3)
58 = 2x + 2x - 6
4x - 6 = 58
4x = 64
x = 16cm
Length = 16cm
Breadth = 13cm 

Hope this helps.
:-)