Imagine you have a bunch of equations with lots of numbers and letters in them, and you want to find out if there is a solution that makes all the equations true at the same time. The Rouché-Capelli theorem helps you figure out if there is a solution or not.
To use the theorem, you first need to organize the equations into something called a matrix. A matrix is like a big table with rows and columns, and each number in the table corresponds to a specific variable or equation.
Once you have your matrix, you can use some fancy math called row operations to simplify it. Row operations are like rearranging the rows of the table or multiplying them by numbers to make it easier to see if there is a solution.
Now here's the cool part: the Rouché-Capelli theorem says that if you do these row operations and the matrix ends up in a certain form (called "reduced row echelon form"), then you can tell if there is a solution or not.
If the matrix is in reduced row echelon form and there are no rows that are all zeros except for the very last number (which represents the right-hand side of the equation), then there is a solution! Yay!
But if there is a row that is all zeros except for the very last number, then there is no solution. Boo.
So basically, the Rouché-Capelli theorem helps you figure out if a bunch of equations have a solution or not, by organizing them into a matrix and doing some fancy math to check for a certain form.