Trigonometry
Angles
What’s the deal with angles anyway?
Before we even get into trigonometry, we need to discuss angles. Don’t worry. Things are not going to get too crazy. I promise.
Let’s go over the basics first.
Degree. One-three-hundred-and-sixtieth of the circumference of a circle. It is also the unit by which we measure angles.
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Angle. This is the space between two intersecting lines.
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Complementary angles. These are two angles whose sum equals 90 degrees.
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Supplementary angles. These are two angles whose sum equals 180 degrees.
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Acute angle. An angle that is less than 90 degrees.
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Obtuse angle. An angle that is greater than 90 degrees.
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Similar angles. It is possible for triangles to each have different sized sides but share the same sized angles. These are called similar angles.
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Right angle. This is an angle that is 90 degrees.
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There is a ton of information about angles that we don’t need to get into. Remember: Try not to overcomplicate things. Just focus on the basics and you’ll be fine.
Next up: Triangles