Algebra and algebraic equations are used sometimes when solving problems and working with formulas.
Everyday algebra is used with it being noticed or even thought about. When we construct or build roads, buildings, airplanes, calculate speeds and so forth, we use algebra.
Maybe you have thought about the concept of speed, distance and time? With a formula you can calculate how far it is, for example, between Stockholm and New York if we know the speed and how long the journey takes in an airplane.
The formula looks like this: