give a decagon( 12 sides) with a circle inscribed that has a radius of 25. find the area of the decagon
A decagon has 10 sides.
A dodecagon has 12 sides.
Assuming you do mean 12 sides.
the area consists of 12 isosceles triangle, with a central angle of 360/12 or 30°
and a radius of 25.
area of one triangle = (1/2)(25)(25)sin 30° = 625/4
but there are 12 of them, so the total area
= 12(625/4) = 1875 units^2