Answer:
This line tells Charles that the point must lie in Quadrant 3 if r is positive or Quadrant 1 if r is negative.
The value of r is negative. Therefore, the point will lie in the opposite quadrant as the angle of rotation.
Step-by-step explanation:
With polar coordinates the first value represents the distance from the origin and the second value represents the rotation from 0. In this case the distance from the origin value is negative, which means it will be in the opposite quadrant to the angle of rotation.
(-5, −3π/4) results in the same point as (5, π/4)
A rotation of −3π/4 results in the same rotation as 5π/4
The rotation results in Quadrant 3 but because the distance value is negative the final resulting point is in Quadrant 1.