Did you know the quadratic formula has many practical applications in everyday situations? It can be used for anything from predicting a sports ball's trajectory to calculating an engine's power output. Scroll down to discover how you can use the quadratic formula to make life a little easier. 1. Calculating Trajectories The quadratic formula is often used to calculate trajectories. This means that when dealing with objects like cannonballs, baseballs and rockets, you can use the quadratic equation to predict where they will end up after being launched.