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    Occasionally you will need to deal with triangles.  Triangular areas are sometimes designed into floor plans and are also sometimes present in residential roofs.  Triangular areas can contribute a uniform increasing load to a structural member.  Most often an increasing load starts at one end of the member as a zero load and increases to the other end where it is at a maximum load.  Complicated or unusual triangular shapes can be solved by trigonometry when encountered. Structural triangles are usually "right triangles" which have one angle equal to 90 degrees.  Here are some short cuts for working with simple triangles...

    All triangles have three angles. The sum of these angles always equal 180 degrees. If you know two of the angles you can solve for the third. Right equilateral triangles have two equal sides and a 90 degree angle.  If you know the length of the two equal sides you can find the hypotenuse (the long side) by multiplying the length of a short side times 1.414.  If you know the length of the longest side, divide it by 1.414 to find the short sides.

The area of a triangle with a 90° corner can be found by multiplying the two short sides and then dividing by 2.  Other triangles can be solved by multiplying the base times the height and dividing by 2.

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