Do you by any chance have a diagram of the circle or the r value?
Answer:
x = 3
Step-by-step explanation:
First, subtract 3x from both sides. That leaves 5x+6=21.
Next, subtract 6 from both sides. That leaves 5x=15.
Lastly, divide by 5 and you get x=3
The tangent function is given by:

Since the angle is in the 3rd quadrant the opposite side and the adjacent side are negative. So, the cotangent function is given by:

Answer:
12/5
I would say D............