Geometry problem: six equal angles on a circle

Leros

Lifer
Jul 11, 2004
21,867
7
81
I have a circle, a straightedge, and a ruler. I need to divide the circle into six equal angles. Like this. Suggestions?

I don't wanna do a bunch of bisections, thats too much work. I haven't had geometry in 7 years.
 

mugs

Lifer
Apr 29, 2003
48,920
46
91
Figure out the lengths of the sides of the hexagon that would fit in the circle
 

Leros

Lifer
Jul 11, 2004
21,867
7
81
Originally posted by: mugs
Originally posted by: Leros
Originally posted by: mugs
Figure out the lengths of the sides of the hexagon that would fit in the circle

Which is just the radius. Doh.

Right. So you figured it out?

yep.

60 degree angle with two equal sides (the two radiuses) means the triangles are equilateral. So it the edge of the hexagon is the same as other sides, which is the radius.
 

Leros

Lifer
Jul 11, 2004
21,867
7
81
Originally posted by: silverpig
You could do it with a compass so easily...

I was working on a project. I had a tape measure and a piece of acrylic to use as a straight edge. I don't have a compass or protractor handy.
 

venkman

Diamond Member
Apr 19, 2007
4,950
11
81
In my day, the teacher gave us a piece of string and a whoopin' to solve this kind of problem.

Kids these days with their fancy cell phones and penicillin.
 

Skyclad1uhm1

Lifer
Aug 10, 2001
11,383
87
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You can draw a square around it, draw straigth lines between the opposite corners of the square, and you'll have the center of the circle. That way you don't even have to know the radius beforehand.
 

alkemyst

No Lifer
Feb 13, 2001
83,769
19
81
Originally posted by: Skyclad1uhm1
You can draw a square around it, draw straigth lines between the opposite corners of the square, and you'll have the center of the circle. That way you don't even have to know the radius beforehand.

That's going to be the right solution. It's going to be the fastest as well.

The hardest part is making sure the square is 'square' to the circle.