Find a cone's missing radius when its V=1477 ft and h= 9 ft.

Octagon=8 sides
so basiclaly you find the piont in the center
draw a dot

then you draw 8 lines from the center to each of the angles

remember that a circle is 360 degrees right?
so now we have a 360 degree angel in the center divided into 8 parts
one angle=360/8=45
we have 8 triangles that are isosoleese (2 sides are equal measure) they have 2 anles of eaqual measure
so
the known angle is not the one that is the same
remember that all angles in a triangle=180 so
x+x+45=180
2x+45=180
subtract 45 from both sides
2x=135
divide by 2
x=67.5
each angle is 67.5 degrees
see attachment