Question

i'll medal and fan for some trig help :)

Answer 1

Whatcha need help with? :)

Answer 2

hi! @johnweldon1993 I'm reviewing for my final for my summer course but misplaced my notes on internal and external angles and have a couple questions about it

Answer 3

No problem...ask away ^_^

Answer 4

so im trying to find the sum of interior angles of a decagon, and if im remembering correctly, the formula is (n-2)180 n being the number of sides

Answer 5

Correct :)

And since we know that a decagon has 10 sides, we just replace 'n' with 10 and evaluate

Answer 6

soooo (10-2)180 --> (8)180=1440?

Answer 7

Correct indeed :)

Answer 8

ok, i have a couple more questions is that ok? :)

Answer 9

of course :)

Answer 10

ok so if each exterior angle is 12 degrees, how many sides does the polygon have? I forget this formula :(

Answer 11

Well we can remember the formula in the sense that ALL polygons have exterior angles that add to 360

So in order to find out how many sides we can use the fact that

\[\large \frac{360}{\text{number of sides}} = \text{length of each side}\]

Answer 12

Did that make sense? :)

Answer 13

Sorry, should have said "measure of each exterior angle" as opposed to "length of each side" kinda confusing context there...sorry about that