Instructions

Figure 10
First, what two things do we have to solve this triangle? We have the hypotenuse because
it is the radius of the arc and the 5° angle. From our tables we see that the 0.0436 was
derived by multiplying the hypotenuse (0.5) times the sin 5°; and the 0.4981 was the
product of 0.5 x cos 5°. This will give us our end-of-arc position.
The 0.0476 has to be calculated to give us the final X-axis point of the angle. We can
easily calculate the 0.5436 because it is the sum of 0.500 and 0.0436. This gives us one
side of the triangle that we know is 5°; therefore the dimension needed is the sin 5° x
0.5436. Adding up these 3 dimensions we end up with the 2.2488 X-axis dimension. We
now have all the numbers we need to generate the code to produce this part.
Take one more look at the complete drawing before starting to write the program. The
main thing I want you to learn is how important it is to solve for the correct triangle to get
the answers you need, and the many times you have to solve more than a single triangle
to solve what may seem as a straightforward problem.
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