[ecshafer]

Yes they do. At minimum Mathematics have a why in that it is something that is arrived at logically, and provable. But when you learn mathematics, whether it be algebra or geometry and trigonometry or calculus or discrete, there is another why added, that of real life solutions. Why do we care about geometry? Well it ends up being useful in optics and physics. We like Trigonometry because it can help you build a building or bridge or shoot a cannon and take down said building or bridge. Calculus has innumerable uses in engineering and physics and finance and biology and everywhere.