What is the sum of the measures of the interior angles of a regular polygon where a single exterior angle measures 72°?

Question

anonymous · Answer

more help please? I know the formula but how do i find out how many sides there are for n?

anonymous · Answer

is it 252?

anonymous · Answer

I did 180n - 72n = 108 and then 360 - 108 = 252?

anonymous · Answer

Wait, I'm confused now too...@campbell_st care to clarify?

anonymous · Answer

To solve for N i just did 108n - 72n = 108 .. then 360 - 108 = 252?

campbell_st · Answer

the sum of the exterior angles of a polygon is 360

there are 2 parts, 

the number of sides( or angles is found by)

 Number of sides(angles)   n  = 360/72

then the interior angle sum is             Angle Sum = (n - 2)*180

anonymous · Answer

Oh. I see...I misread the question :/

campbell_st · Answer

ooops n = number of sides

anonymous · Answer

i thought so. so how do i solve for N first?

anonymous · Answer

Yup. Following what ^ said, 360/72 = n. If so, what is n?

campbell_st · Answer

yes thats correct,,,,

anonymous · Answer

So N = 5

anonymous · Answer

Yes. Now, plug it in here:
$$(n - 2)180$$

anonymous · Answer

540?

anonymous · Answer

Yes :)

anonymous · Answer

ah, thankyou ! :D

anonymous · Answer

np :)