ELI5: Explain Like I'm 5

Simultaneous equations models

Okay kiddo, we're going to talk about a type of math problem called simultaneous equations. In this type of problem, we have two or more equations with two or more variables, and we want to find the values of those variables that satisfy all of the equations.

Now, imagine we have a situation where we have multiple equations that all rely on each other. For example, let's say we have three friends who are all going shopping together. We know that each friend has a certain amount of money to spend, but we don't know exactly how much. We also know that all of their combined spending will equal the total amount of money they have altogether.

To solve this problem, we need to use a simultaneous equations model. We would set up three equations, one for each friend's spending, and use variables to represent their unknown amounts of money. Then we would set up another equation that represents the total spending of all three friends combined, using the same variables.

Once we have all of these equations, we can use algebra and some fancy math techniques to solve for the variables and find out how much each friend has to spend. This is what we call a simultaneous equations model - it's a way of solving a complex problem by breaking it down into smaller, interconnected parts.

There are lots of real-world situations where simultaneous equations models are useful, from economic forecasting to engineering and beyond. The key is to identify all of the variables and equations that are involved in the problem, and to use a systematic approach to solve for them all at once.