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How to Find a Side of a Right Angle Using Degrees

Degrees are a measurement unit used widely in trigonometry to measure angular distance. Due to the proportionality of a triangle's sides with its three angle measures, a triangle's sides can be determined using angle measures in degrees. These measures, along with inverse trigonometric functions, are taught in introductory trigonometry courses and in navigation. This technique also finds use in fields such as topology, surveying and construction.

Scientific calculator

Instructions

- 1
  Choose one of the smaller angles. The angle chosen must not be the 90-degree angle.
- 2
  Take the sine of the angle. This is performed on any standard scientific calculator by pressing the "sine" or "sin" key and entering the angle in degrees. The resulting value is the length of the side opposite to the angle.
- 3
  Take the cosine of the angle. This returns the length of the side adjacent to the angle. The standard scientific calculator button for this operation is either "cosine" or "cos."
- 4
  Divide the sine value by the cosine value. This returns the value of the hypotenuse side of the triangle.

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