The only quadrant where `tan\ theta`* *is negative and `csc\ theta`* *is
positive is the **second** quadrant.

First, we find the reference angle:

Let tan *α* = 0.809 then *α* = arctan 0.809 = 39.0°

So *θ* = 180° − 39.0° = 141.0°

So cos *θ* = -0.777

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