Regular pentagons A and B are similar. The apothem of pentagon A is equal to the radius of pentagon B. Compare their areas.

This question is really confusing. Any help would be great!

Respuesta :

What the question means is 
Regular pentagon A is a larger regular pentagon B, in such a way that
the apothem of A coincides with the "radius" of pentagon B, which is actually the distance from the centre to a vertex of B.

The figure attached shows the situation, where regular pentagon A is the lighter figure, and pentagon B is the darker one inside A.

The ratio of the areas depends on the ratio of the apothems.
The ratio of an apothem to the "radius" is the ratio sin(108/2)=sin(54), since the interior angle of a pentagon is 108 degrees.

The ratio of areas of B to A is the square of the ratio of the apothems, namely sin^2(54)=0.809017^2=0.654508
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