# Geometry Help

A

#### amdx

Jan 1, 1970
0
I'm trying to draw a 7 sided polygon using MS Paint.
I found a program that is supposed to allow me to draw any angle
in Paint.
I'm starting to question it's accuracy because of all the problems I'm
having.
But assume for now the program is accurate.
I have tried 25.71*, 54.43*, 64.285*,
If I start with a vertical line, then rotate it to (x) angle,
What is (x) angle so I can add it to itself 6 time to make the 7 sided poly.
http://i395.photobucket.com/albums/pp37/Qmavam/7sidedpolygon.jpg
Here's a visual.
Thanks, Mikek

PS. electronics related, making an inductor form, similar to this six sided
form.
http://i395.photobucket.com/albums/pp37/Qmavam/3Dcoil24wiresideview.jpg

M

#### Martin Brown

Jan 1, 1970
0
I'm trying to draw a 7 sided polygon using MS Paint.
I found a program that is supposed to allow me to draw any angle
in Paint.
I'm starting to question it's accuracy because of all the problems I'm
having.
But assume for now the program is accurate.
I have tried 25.71*, 54.43*, 64.285*,
If I start with a vertical line, then rotate it to (x) angle,
What is (x) angle so I can add it to itself 6 time to make the 7 sided poly.

You need to add it to itself 7 times to make a heptagon.

N-gon 3 4 5 6 7 8 N
Angle 120 90 72 60 51.4285 45 360/N
http://i395.photobucket.com/albums/pp37/Qmavam/7sidedpolygon.jpg
Here's a visual.
Thanks, Mikek

PS. electronics related, making an inductor form, similar to this six sided
form.
http://i395.photobucket.com/albums/pp37/Qmavam/3Dcoil24wiresideview.jpg

A six sided one would be a lot easier to build!

Regards,
Martin Brown

T

#### The Great Attractor

Jan 1, 1970
0
You need to add it to itself 7 times to make a heptagon.

N-gon 3 4 5 6 7 8 N
Angle 120 90 72 60 51.4285 45 360/N

A six sided one would be a lot easier to build!

Regards,
Martin Brown

http://tinyurl.com/3z7c52n

A

#### amdx

Jan 1, 1970
0
Martin Brown said:
You need to add it to itself 7 times to make a heptagon.

I don't know, maybe semantics if I have one and add it to itself six times,
I have 7.
N-gon 3 4 5 6 7 8 N
Angle 120 90 72 60 51.4285 45 360/N

I don't know what those two lines are supposed tell me.

Here's the program I'm rotating with.

A six sided one would be a lot easier to build!

It was, now I want 7 sides.

K

#### [email protected]

Jan 1, 1970
0
I don't know, maybe semantics if I have one and add it to itself six times,
I have 7.

But you have to go 360 degrees to get back where you were. For a triangle,
you have to turn three times, 120 degrees each to get back to the original
bearing.
I don't know what those two lines are supposed tell me.

For each N-gon (first row) the angle (second row) you need to turn at each
corner to complete the N-gon. For a triangle (equilateral) at each corner you
would turn 120 degrees (60 degree interior angle).

360/7 = 51.42857 change in direction, or an interior angle of 128.57143
degrees.

A

#### amdx

Jan 1, 1970
0
But you have to go 360 degrees to get back where you were. For a
triangle,
you have to turn three times, 120 degrees each to get back to the original
bearing.

For each N-gon (first row) the angle (second row) you need to turn at each
corner to complete the N-gon. For a triangle (equilateral) at each corner
you
would turn 120 degrees (60 degree interior angle).

360/7 = 51.42857 change in direction, or an interior angle of 128.57143
degrees.

I have spent time working with 51.43 and I'll try some more.
So I start with a vertical line and rotate it to 51.43, now for the second
side,
do I add 51.43 + 51.43 = 102.86? If so, I'm feeling the rotation program
isn't
working for my need. If I can get 3 sides I can flip it horizontal for the
other 3 sides,
and then draw in the bottom.
Thanks, Mikek

T

#### The Great Attractor

Jan 1, 1970
0
Hi John,
I have one try at 51.43 and it could be right for the top left and right
sides, but what is the next angle
From vertical? It measures around 12 degrees but doesn't work when using the
program.
Could be I'm not using the program for it's designed purpose.
Thanks, Mikek

Use a 7/2 or 7/3 method:

halfway down the page.

http://en.wikipedia.org/wiki/Heptagon

S

#### Spehro Pefhany

Jan 1, 1970
0
I'm trying to draw a 7 sided polygon using MS Paint.
I found a program that is supposed to allow me to draw any angle
in Paint.
I'm starting to question it's accuracy because of all the problems I'm
having.
But assume for now the program is accurate.
I have tried 25.71*, 54.43*, 64.285*,
If I start with a vertical line, then rotate it to (x) angle,
What is (x) angle so I can add it to itself 6 time to make the 7 sided poly.
http://i395.photobucket.com/albums/pp37/Qmavam/7sidedpolygon.jpg
Here's a visual.
Thanks, Mikek

PS. electronics related, making an inductor form, similar to this six sided
form.
http://i395.photobucket.com/albums/pp37/Qmavam/3Dcoil24wiresideview.jpg

~64.286 degrees is correct.

The sum of interior angles in a polygon is (n-2) * 180°, so you want

1/2 * 1/7 * (5 * 180) degrees = 450/7 degrees.

Maybe try something other than MS paint, like a real CAD program?

Best regards,
Spehro Pefhany

K

#### [email protected]

Jan 1, 1970
0
I have spent time working with 51.43 and I'll try some more.
So I start with a vertical line and rotate it to 51.43, now for the second
side,
do I add 51.43 + 51.43 = 102.86? If so, I'm feeling the rotation program
isn't
working for my need. If I can get 3 sides I can flip it horizontal for the
other 3 sides,
and then draw in the bottom.

You increment the bearing 51.43 degrees at each corner if the drawing program
uses absolute directions. If it uses relative directions you just use the
51.43 degree number. "Flipping" it just adds confusion.

R

#### Rich Grise

Jan 1, 1970
0
amdx said:
I'm trying to draw a 7 sided polygon using MS Paint.
I found a program that is supposed to allow me to draw any angle
in Paint.
I'm starting to question it's accuracy because of all the problems I'm
having.
But assume for now the program is accurate.
I have tried 25.71*, 54.43*, 64.285*,
If I start with a vertical line, then rotate it to (x) angle,
What is (x) angle so I can add it to itself 6 time to make the 7 sided
poly. http://i395.photobucket.com/albums/pp37/Qmavam/7sidedpolygon.jpg
Here's a visual.
Thanks, Mikek

PS. electronics related, making an inductor form, similar to this six
sided form.
http://i395.photobucket.com/albums/pp37/Qmavam/3Dcoil24wiresideview.jpg

Use your calculator or a small program or script (it could probably be
done on a spreadsheet) that gives you coordinates for the points, then draw
them while referring to the "x,y" display on your paint program, then
connect the dots.

Have Fun!
Rich

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