Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

ok, I am working on a math problem. I got the solution by making a right angle. However I am not allowed to do that because the contrains are that it must be done only with a straight-edge.

Let's say I have a Hexagon with vertices A and B opposing each other. How to I make a ray starting at B which is at an right angle to the ray AB? With proof please :D

share|cite|improve this question

You can easily extend the triangular grid defined by the haxagon: Let $A,B,C,D,E,F$ be the vertices of the hexagon (I prefer these "logical" names, so your opposing vertices are $A,D$ instead of $A,B$).

Let $AF$ and $CE$ intersect in $G$, let $EF$ and $CD$ intersect in $H$. Let $GH$ and $BE$ intersect in $I$. Then $ID\perp AD$. The proof is straightforward as all points belong to the grid. enter image description here

share|cite|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.