The internal angle at any vertex of a regular -gon is:Originally Posted byChuck_3000

If regular -gons with sides constitute a point-fill set then

the sum of the internal angles at their vertices sum to radians, that is:

or:

.

Now lets look at part (a).

, and , so plugging these into equation and simplifying:

then trial and error will allow you to find and to complete the point fill set.

RonL