Question

The system of equations shown is solved using the linear combination method What does 0 = 0 mean regarding the solution to the system?

Answer 1

Example case:

$\begin{cases}x+y=1\\2x+2y=2\end{cases}$

The second equation is twice the first, so subtracting that from the second equation yields the identity 0 = 0.

This is an identity. It's an equation that holds true (clearly, 0 is the same as 0) regardless of the values of the variables, which means any pair of numbers $(x,y)$ is a solution to the system.