1.9-gon
2.11-gon
please also explaing how you got your anwser.
2006-11-03 09:20:37 · 4 answers · asked by ♥Roberta. 5 in Education & Reference ➔ Homework Help
for a polygon with n sides, the sum of all interior angles would be 180*(n-2) degrees.
So a nonagon would be 180*(9-2) = 180*7 = 1260 degrees
an 11-agon would be 180 * (11-2) = 1620 degrees
2006-11-03 09:26:59 · answer #1 · answered by disposable_hero_too 6 · 0⤊ 0⤋
The sum of the internal angles of apolygon is 2n-4 right angles or (2n-4)X 90 degrees,where "n" is the no, of sides of the polygon.Therefore, a 9-sided polygon(or nenagon)has (2*9-4) or 14 right right angles or 14X90 degrees=1260 degres.Similarly an 11-gon has 2*11-4 or 18 right angles or 1620 degrees as sum of its angles.
2006-11-03 19:56:29 · answer #2 · answered by alpha 7 · 0⤊ 0⤋
Any polygon with n sides can be divided into (n - 2) distinct triangles by drawing all the distinct diagonals from a single vertex (corner). Since each of the (n - 2) triangle is 180 degrees, the sum of the interior angles will always be 180(n - 2). Try it for yourself by drawing some examples :-)
Good Luck!
2006-11-03 18:23:25 · answer #3 · answered by math maker 2 · 0⤊ 0⤋
the sum is (n-2)*pi
1.9-gon=7pi
2.11-gon=9pi
2006-11-03 17:23:37 · answer #4 · answered by raj 7 · 0⤊ 0⤋