Find the sum of the measures of the interior angles of the indicated convex polygon 21-gon

Sum of all interior angles on a polygon is 

180( n - 2)     n = number of sides in the polygon.

now, this one is is a 21-gon, thus the sum is 180( 21 - 2).

Arhombus is a quadrilateral.

step-by-step explanation:

when the line is solid:

it's either < or >

when the line is dashed:

it's either < or >

this > inequality sign means:

greater thanmore thanaboveexceeds

this < inequality sign means:

less thanfewer thanbelow

this > inequality sign means:

greater than/equal tono less thanat leastminimum of

this < inequality sign means:

less than/equal tono more thanat mostmaximum of

about the problem:

since the line is solid, that means it's either < or >

srry i'm not done ! i'll