how to solve a polygon '

help fo polygon 

Let n be the number of sides of each polygon.

For angles...

Size of each angle = $\frac{(n-2)(180)}{n}$(in degrees)

For perimeters and areas(i love area questions :D)

Let n be the number of sides of each regular polygon and x be the length of each side

Perimeter = nx

Also I invented some of the area formulas to get the area of regular polygons(Length of each side = x)

(all trig functions in degrees)

Regular pentagon: $(x^2sin72)(1+cos36)$

Remarks: The original regular pentagon area formula needs to know the apothem but my formula need not. 

Regular hexagon: $3\sqrt{3}x^2\times\frac{1}{2}$

Regular octagon: $(2x^2)(1+\sqrt2)$

I found this all in one day. I used trigonometric functions when finding the regular pentagon and hexagon area formula and pythagoras theorem when finding the regular octagon area formula. Hope this can help you :D