Applying Radical Equations To Real-life Scenarios..?

My teacher is not helping me at all, so I’m desperately relying on the Yahoo! Answers Community. Please, help me. I am in a frustrated state and am so bewildered. I’m not trying to get some sympathy, but I just don’t know what to do for this. I mean, some teachers my generation of technolody can just use the Internet so easily to obtain information, but it’s not exactly like that.
Please, can somebody give me a thorough example of applying Radical Equations to real life scenarios? I need at least three, and I just can’t figure out how this specific lesson can be applied to anything.