What is the perimeter of a polygon with sides measuring; (a) cm,(a+1) cm; (a+2) cm and 3(a+3)?

To find the perimeter of a polygon, simply add the sides.
Here, the sides are: a, a+1, a+2, and 3(a+3)
So,

Now, do the distributive property and combine like terms,

The answer is 6a + 12. Hope this helps and have a terrific day!

I’d say letter a..