How any why are the media and politicians dependent on each other?

Hey there! :) 

The media and politicians are very dependent on one another simply because while the media wants to get the word out as fast as possible, politicians want the word out as fast we possible as well, but they also want it to be accurate. The media tends to give out information that is slightly altered or incorrect in some way or another, and politicians want their information to be as correct as possible. 

Politicians rely pretty heavily on the media to get the word out if something happens, and use the media quite simply to communicate with others not apart of their social standing. On the other hand, the media relies on politicians for news articles/stories and simply for gossip. 

A fantastic example of the media depending on politics is during President Trump's 'Fake News' era. This was televised pretty much globally, as the media wanted to make fun of Trump's words, and it was a huge thing - because he's the president! Due to the fact that Trump kept tweeting silly things, the media had tons of things to say about him - resulting in more media viewers.

~Hope this helped!~