## In the Real World

After all of this learning about systems of equations, you might be wondering what this has to do with real life. Prepare to be amazed at the connections to the real world.

Systems of linear equations are used in the real world by economists and entrepreneurs to find out when supply equals demand. It's all about the mulah, and if you don't know the numbers when you have a business, it might fail.

Whoever said life was linear? Most real-life equations are actually non-linear, like throwing a ball up high. Picture yourself throwing a tennis ball into the air, then one or two seconds later, another ball You could use a system of non-linear equations, in this case quadratic equations, to find out when two balls would be the same height.

An abstract concept we covered in this section involved partial fractions. This topic seems unconnected with real life, but we can really use this in calculus. In calculus, we get area under curves by a method called integration. When finding the area of a crazy algebraic fraction, it helps to break the fraction into smaller chunks to make integration easier.

Why would we need to find the area under a curve? That's a whole other topic, but you might be painting a huge mural on the side of a building and need to calculate the painted area of a curve to determine the amount of paint to buy. Depending on the complexity of the curve, you might have to use partial fractions to help you integrate. There, now you should feel better about partial fractions.