Let’s solve the system of equations step by step using substitution:

The system of equations:

1. $x = y$
2. $x - 2y = 7$

Step 1: Substitute $x = y$ into the second equation

Replace $x$ with $y$ in the second equation: $y - 2y = 7$

Step 2: Simplify

$- y = 7$

Step 3: Solve for $y$

$y = -7$

Step 4: Substitute $y = -7$ back into $x = y$

Since $x = y$, we have: $x = -7$

Final Answer:

The solution to the system is: $(x, y) = (-7, -7)$

Would you like further explanation or details?

Here are 5 related questions to explore further:

1. How do we verify the solution of a system of equations?
2. What are other methods to solve systems of equations besides substitution?
3. How can substitution be used for non-linear systems of equations?
4. What happens if a system of equations has no solution or infinitely many solutions?
5. How do systems of equations apply to real-world problems?

Tip: Always substitute your solution back into the original equations to verify its correctness!