Final answer:
The fault and auxiliary planes that separate seismic-wave radiation into compressional and extensional quadrants are planes at right angles to each other.
Step-by-step explanation:
The fault and auxiliary planes that separate the seismic-wave radiation into compressional and extensional quadrants are planes at right angles to each other. The fault plane is where the rock breaks and slips, causing an earthquake. The auxiliary plane is a secondary plane that complements the fault plane.
When seismic waves are radiated from the fault plane, they are divided into compressional and extensional quadrants based on the orientation of the fault and auxiliary planes.