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Trig Problem need someone to explain this

  1. Mar 8, 2004 #1
    Given 2 angles of a triangle, how many triangles are possible? Explain why.

    Seeing how a triangle is 180 degrees, and if they give you two angles, that automatically locks the 3rd one at a certain value that will equal 180 when added with the other 2 angles. So I get 1.

    My other idea was that it was infinity since you can divide the triangle with the two given sides into infinite smaller pieces as you get smaller and smaller.

    I also think I might be missing a big point which is taking into consideration the sides of the triangle.

    Any help would be very appreciated.
  2. jcsd
  3. Mar 8, 2004 #2
    Given 2 angles you can automatically get the third angle. So the angles and shape are fixed. However you can double each side and get the same shape. You could also triple the size, or as you say shrink the size etc. So their are an infinite number of triangles of different size but the same shape. The formal name for triangle with two equal sides is " similar triangles". The only slightly tricky thing in this area that your teachers may be ruthless is that if that given two sides and an the non-included angle you can make actually make two triangles. People ignore the fact that if the non included angle is greater than 90 degrees
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