Help with Directional 2D Cone

I am prototyping a first attempt at a top down game and hope someone might point me to some code examples.

I have figured out how to create a simple 2D cone shape, but I am not sure how to center it in a particular direction. The cone will eventually indicate the direction, and margin of error for a ranged attack, centered in the opposite direction of another position set behind the cones origin. Much like lining up a telescope.

Of course, I have to start by simply being able to direct the cone to begin with... and so far, everything I have tried has failed pretty badly. I do not have a very strong grasp of trig, but I learn fast.

Here is my code: It will draw a simple cone using LineRenderer quite well.

 private void DrawLineCone(Transform origin, float angle, float radius)
 {
     int points = 3;
     Range = radius;

     float radian = angle * Mathf.Deg2Rad;
         //Debug.Log("Rad:\t" + radian + " Angle:\t" + (Mathf.Rad2Deg * radian) );
     float radianFract = radian / (float)points;
         //Debug.Log("Fract:\t" + radianFract);
     Vector3 center = origin.transform.position;    //Where unit stands
     
     lineRenderer.SetVertexCount(points + 3);    //Add start/finish points

     Vector3 vect = center;    //Start point is center point.
         lineRenderer.SetPosition(0, vect);

     for(int x = 0; x < points + 1; x++)
     {
         vect = center;
             vect.x += (float)(Math.Cos(radianFract * x) * Range);
             vect.z += (float)(Math.Sin(radianFract * x) * Range);

         lineRenderer.SetPosition(x + 1, vect);    //Skip first/last points.
     }
     
     vect = center;
     lineRenderer.SetPosition(points + 2, vect);    //Last point is center point.
 }