Answer:
-90° = 3π/2 radians
Explanation:
Keep in mind that -90° represents a 90° clockwise rotation from the positive x-axis. This is the same as a 360°-90°=270° counter-clockwise rotation from the positive x-axis.
To convert from degrees to radians, we simply multiply the degrees by π/180 radians. So, the answer is (270)(π/180)=(270π/180)=3π/2 radians