e. A number squared decreased by 2

The expression "a number squared decreased by 2" can be mathematically represented as \( x^2 - 2 \), where \( x \) is the number. This kind of expression can lead you into the fascinating realm of quadratic functions. Essentially, you can graph this equation, and you'll notice that it creates a beautiful 'U' shape known as a parabola. In the real world, this type of expression often appears in physics, especially in projectile motion! When you drop an object, its height can be modeled using a quadratic function. By analyzing the equation, you can determine how far the object falls after a certain amount of time, making it not just a mathematical curiosity but also a practical example in the laws of motion!