The angle formed will be acute angle as the angle is less than 90 degrees. This line will be perpendicular to PQ . The points connected on the locus will form a semi circle. To draw the angle vertex is identified and then a line is drawn on it to form an angle.
The quadrants go right to left. The 1st quadrant is the top right. The 2nd quadrant is the top left. The 3rd quadrant is the bottom left. The 4th quadrant is the bottom right.
If you graph the point (-4,5) your point would end up in the 2nd quadrant.
becomes 
