Sides of an OctagonDate: 04/13/97 at 11:35:29 From: Jeremy Gilick Subject: Octagon sides What is the formula for the length of the sides of an octagon whose diameter is 15 feet? I've tried to find a formula but can't seem to find one. Date: 04/13/97 at 18:19:30 From: Doctor Steven Subject: Octagon sides You can draw eight congruent triangles emanating from the center of the octagon. These eight triangles should be isosceles and and each will have a central angle of 45 degrees. This means the other two angles in each triangle will be 67.5 degrees. The two like sides of each triangle are the radius of the octagon, or 7.5 feet. Use your knowledge of triangles to find the height of these triangles and that will be your distance from the center of the octagon to the center of the sides. Find the length of the third side of the triangle and that is the length of the sides of the octagon. -Doctor Steven, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
Search the Dr. Math Library: |
[Privacy Policy] [Terms of Use]
Ask Dr. Math^{TM}
© 1994-2013 The Math Forum
http://mathforum.org/dr.math/