area of rectangle a is 2 times that of rectangle b that means 2x+x = 36cm^2
3x = 36cm ^2
x = 36/3
x= 12cm^2
and 2x = 24cm^2
now side of square = are divided by sides = 36/4 = 6cm
that means length of rectangle a and b is 6cm too
now for rectangle a,
l*b = area
= 6*y=24
y=24/6 = 4
therefore dimensions of rectangle a are- length = 6cm, breadth = 4cm
and for rectangle b, length = 6cm and breadth = 6-4 = 2cm.
hope this .