In this video, we meet Slash McFender, a rock 'n' roller with a habit of forgetting his guitar at home. Slash has the brilliant idea to use his chest hairs for strings (gross, we know, but he had a show in fifteen minutes, okay?). Learn how to use inverse variation and the constant of proportionality to compare the vibration frequency of his chest hairs to the length of his chest hairs. If Slash’s new musical method catches on, we might be rocking out in our garages using our armpit hair in the near future. Shudder.