Tan is short for tangent. Here we tell you what tan 20 degrees is, how we came up with the answer,
and how knowing tan of 20 degrees can be useful.
To calculate tan (20) degrees of a right angled triangle, we use the following
equation where angle is 20:
Tan(angle) = Opposite/Adjacent
Tan 20 degrees is simply the ratio of the side opposite of the angle to the side
adjacent to the angle. As long as the angle stays at 20 degrees, the ratio does not
change and tan 20 degrees is a fixed number. See figure 1 for a better illustration.
The answer to "What is tan 20 degrees?" is as follows:
Tan(20) = 0.364
Now you also know that the following is true:
0.364 = Opposite/Adjacent
This is useful because if you know either Opposite or Adjacent length,
you can enter it in the equation above and solve for the missing length.
You can also rewrite the equation above to solve for Opposite and Adjacent to get the
following new equations:
Opposite = 0.364 x Adjacent
Adjacent = Opposite / 0.364

