Please Answer

Could someone please show me how to solve this Prove tan(-theta) = -tan(theta)

I just have a question for the people who help the students. Do you guys pick certain people to answer or does it take more time to figure out or answer certain problems over others? Or does it just have to do with the fact that some tutors and volunteers...

Okay, thank you so much! I was just curious and that makes a lot more sense now. Thanks for answering!

I don't have much time. 30 min left