polygons

  1. S

    Two Problems (Area of Polygons?)

    We are currently reviewing the area of polygons (triangle, rectangle, parallelogram, trapezoid, etc.) and none of the material we learned in class helped me with these two problems. For the parallelogram, the answer is 1/16, but I only found this from looking in the book for the answers. I am...
  2. B

    Constructing polygons on the sphere

    Hello, I want to construct polygons on the sphere \mathbb{S}^2\subset\mathbb{R}^3, but I do not know how to do it systematically. For instance for quadrilaterals: Given four angles \alpha, \beta, \gamma, \delta and a fixed Perimeter P. I want to construct or find all quadrilaterals with the...
  3. Q

    Star-shaped polygons not of the form {n,m}?

    Is there a name for a 'regular' star-shaped polygon where alternate vertices lie on one of two radii, but where the edges don't necessarily follow the {n,m} pattern?
  4. C

    Similar Polygons

    Hey Guys, For number 19) I ended up getting 49 for the measure of angle L But it's wrong since the correct answer is 90. What I did is just combine all of the given into an equation and give it an equals value of 360 Doesn't work since I got the answer wrong. (Angry)
  5. E

    Equilateral triangle and inscribed circles, mixed polygons, just my favorite...

    There is an equilateral triangle that is shaded except for the inscribed circle smack in the middle. The radius is 8 and I have to find the shaded area's area.
  6. P

    Confusing questions - angles in polygons

    I need some help on this maths question, it would be much appreciated - Q. Five of the angles of a hexagon are eqaul to eachother and each is greater than the remaining angle by 72 degrees, find the size of the smallest angle. Also this question- Q.Th angles of a qaudrilateral taken in order...
  7. W

    About polygons problem

    How to prove that a+b+c+d+e = 540°? Can anybody help? Thanks
  8. W

    Polygons problem

    What is the formula of question (a) to find y? and how to prove that triangle ABE is similar to triangle ADC? Can anyone help me, thank you.
  9. Mathhead200

    Ellipses and Equiangular Polygons

    - Is it possible to inscribe a unique ellipse with maximal area into any arbitrary equiangular polygon? - Is it possible to circumscribe a unique ellipse with minimal area around any arbitrary equiangular polygon? - Are those inscribed and circumscribed ellipses similar (in the geometric sense)...
  10. Z

    Mathematica, Graphics: Union of Polygons and Opacity Settings

    Dear all, I am trying to draw a set of polygons in Mathematica (version 8). These polygons intersect, and I do not mind per se that Mathematica (apparently) has no implemented function to compute the union of a set of polygons, as I can always draw all the polygons combined and will get what I...
  11. Z

    Theorems about Similar Polygons?

    Theorems about Similar Polygons? I so need help with this and couple of others, PLEASE HELP ME! Explain this to me Given: rectangle ABCD is similar to rectangle ZBXY. Enter answer as a mixed number. here's the image link ImageShack® - Online Photo and Video Hosting If BC...
  12. N

    similarity of two polygons

    Hello friends, Lets say I have 10 different polygons with different shapes but I know that all have 4 edges. A new polygon comes into play which also has 4 edges. I need to find out, which of the polygons are more similar in shape to the new one. Thank you in advance for your help...
  13. S

    Interior and Exterior Angles of Polygons

    Hi everyone, I'm having trouble completing the following chart. Please help. # of Sides sI = Interior Sum AI = Interior Angle Ae= exterior angle 3 _ _ _ 4 _ _...
  14. M

    Finding the perimeter and area of polygons

    I need to find the perimeter and area of polygons. I do this by inscribing them in a circle. I need to do this for 3, 6, 9, 12, and 15 sided. Is there some kind of pattern or relation?
  15. S

    [SOLVED] 7 and 11 sided polygons

    What's another name for a 7 sided polygon? Heptagon and what..? What's another name for an 11 sided polygon? (there's two names) Thanks! :)
  16. E

    [MATLAB] Delaunay/Veronoi Diagram - Get polygons

    I am trying to calculate polygons around nodes to provide criteria for where the nodes can move during an optimization routine I am working on. Nodes are restricted to the square region u={0,1} and v = {0,1}. Here is the code for the attached image. It is simply a delaunay triangulation and...
  17. D

    Differentiating a formula for area of polygons

    Hi guys :) Could someone please tell me how to differentiating this particular formula with step by step directions? A=(22500/n)/tan(Pi/n)) Thanks in advance. As soon as possible if you can :)
  18. V

    Geometry with Polygons..

    I would be very thankful if somebody could work and explain these problems. They are part of my Math SAT prep and I don't understand them.
  19. J

    Equilateral polygons and right angles

    Help, I cannot draw this shape from its description: 1) Draw an equilateral right pentagon, with exactly 1 right angle and has at least one line of symmetry. And I don't know how to prove this: 2) Explain why any equilateral right pentagon (i.e including the one above) cannot have more than...
  20. D

    Creating irregular polygons

    Is there any software or other way of creating irregular polygons using given dimensions (circumference - but preferably radii)? I would like to colour them in and add text or other graphics when they have been created.