How to find the sum of the measures of the interior angles of a figure?

Well, heres the question i need help on





Find the sum of the measures of the interior angles of the figure.





The figure is a 5 sided polygon.





Please explain how you did it! thankes





Oh and the choices i have are





either


-540


-1260


-900


-720How to find the sum of the measures of the interior angles of a figure?
you take 5 subtract 2 from it which gives you 3 multiply that by 180 which gives you 540 and thats the sum of the angles.How to find the sum of the measures of the interior angles of a figure?
Take any point inside the pentagon, and join it to each of the vertices, so making 5 triangles. The sum of the angles of one triangle is 180 degrees, so the sum of the angles of 5 triangles is is 5 x 180 = 900 degrees. But, you have included here the angle at the point inside the pentagon which is 360 degrees, so you have to subtract that from 900, to give:





900 - 360 = 540 degrees.





Hope this helps, Twiggy.
ya
I think it's 540 degrees
what nina said.





and it's really important that you remember this formula. they ask it on ALL of the standardized tests!
The formula is (n-2)180.


n=the number of sides the polygon has
it is 180(sides-2)


thatsa the eqation i think