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Homework Help: Drawing Angles: Easy Question

  1. Oct 25, 2004 #1
    Does anyone know a site that shows how to draw angles using only a ruler and a compass?

    60 degree, 35 degree, 45 degree angels ect.

    Any explaination on how to do this would be great. I have to show curves to signify that I used the compass and I believe the method involves a point of intersection.

  2. jcsd
  3. Oct 25, 2004 #2


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    Gold Member

    Imagine a x/y coordinate plane with a line segment going out [tex]\theta[/tex] counterclockwise from the positive x-axis. You can use the fact that the tangent of that angle will give you the slope of that line to figure out the x and y distance you have to go to make that angle.

    If that's not clear, just draw a triangle and label your theta. Using trig functions you can find the possibilities for the sides.
  4. Oct 25, 2004 #3
    Drawing a 45 degree angle is easy if you know how to bisect an angle (you use two coordinate axes).
  5. Oct 25, 2004 #4
    Define A value for one of your sides use trig to find the value for the other two sides given an angle.

    From this set your compas to your first desired length draw a circle
    then set the compas to the second length pick a point along the first circle draw your next circle
  6. Oct 25, 2004 #5
    I finished my bonus sheet, I appreciate everyone's help.
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