My math teacher didn't explain how to do this stuff and I've been struggling to understand what it is for like the past half hour. Please help. (sorry its a PDF there was no other easy way)

The architect's side view drawing of a saltbox-style house shows a post that supports the roof ridge. the support post is 8 ft tall. the distance from the front of the house to the support post is less than the distance from the post to the back of the house. how far from the front of the house is the support post positioned?