In two similar polygons, the ratio of their areas is the square of the ratio of their sides. If the sides of any polygon are a and b then :
Ratio of area =[tex] a^{2} :b^{2} [/tex]
Given ratio of area =81:64
Or 81:64=[tex] a^{2} :b^{2} [/tex]
Taking root of both sides
9:8=a:b
The ratio of perimeter of any two similar polygon is equal to the ratio of sides.
Ratio of perimeter = a:b
Perimeter of first polygon is 32 cm.
Let the perimeter of second polygon be x.
32:x=a:b
Or, 32:x=9:8
[tex] \frac{32}{x} =\frac{9}{8}
[/tex]
Cross multiplying
9x= (32)(8)
9x=256
Dividing both sides by 9
x=28.4.
The perimeter of second polygon is 28.4cm.