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# Angles question help

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1. Apparently y is 149* but I don't understand why! Please could someone explain how you would work this out, thankyou!
2. (Original post by rm715)
y is 149* but I don't understand why!
Lol I did a pun and I didn't notice
3. Interior angles in a hexagon add up to 720.
4. Yeah, interior angles add up to 720, subtract all of those angles from 720 to give 149.

Also, to work out the sum of the interior angles, you do (n-2) x 180 (because you can split the shape into triangles, technically).
5. Ahh I get it, thankyou. So a hexagon's interior is just 360x2
6. (Original post by rm715)
Ahh I get it, thankyou. So a hexagon's interior is just 360x2
The sum of the interior angles of an sided polygon is . In this case, so .
7. (Original post by rm715)
Ahh I get it, thankyou. So a hexagon's interior is just 360x2

8. (Original post by notnek)

I thought it was a dodecagon why did I get it wrong
9. (Original post by rm715)
I thought it was a dodecagon why did I get it wrong
The formula to find the sum of the interior angles of a polygon is

Sum = ( Number of sides - 2 ) x 180

A dodecagon has 12 sides. So for a dodecagon :

Sum = (12 - 2) x 180 = 10 x 180 = 1800.

So it can't be a dodecagon.

By the way, the use of the word 'regular' in this question is unnecessary. Non-regular polygons have the same sum as regular polygons.

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