Got offered a job at Guitar center as a guitar instructor. Are they lowballing me? ($11.60hr)

I've been applying to several music studios in Texas (Dallas) and unfortunately I haven't been able to get in contact with many people. So obvious I went to guitar center and applied for a guitar instructor position. The manager is saying that I would receive $9 base pay in between lessons and $11.60 per hour for lessons. I was even under the impression that was per half hour lesson. Obviously they would try to minimize the gaps in between. However...based off all research it seems like they are extremely lowballing me and that $20 an hour is below national avg. If you do work there or at least know the area...what is a fair payment? Btw this is located in Texas.

EDIT: Wow!! I did not expect this thread to blow up! I just posted it out of being upset after taking time to go through a process. I'm new to this (guitar) world but been playing for a while. Thank you all for the information and help and I'm so grateful there are good people out there willing to help regardless of how. I'm taking my time going through this thread and gonna respond to as much as I can.