Let's solve the equation step by step:

Equation: $2x - x = 7 + 5$

Step 1: Simplify both sides of the equation.

• On the left side: $2x - x = x$.
• On the right side: $7 + 5 = 12$.

So the equation becomes: $x = 12$

Final Answer:

$x = 12$

Would you like further explanation or have any questions about this solution?

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Here are 5 related questions to explore:

1. How do you solve equations involving fractions like $\frac{2x}{3} - x = 4$?
2. What happens if there is more than one variable, like in $3x + 4y = 10$?
3. How do you check your solution after solving an equation?
4. How do you solve quadratic equations like $x^2 - 5x + 6 = 0$?
5. What is the difference between solving linear equations and solving systems of equations?

Tip: Always simplify both sides of the equation first, and combine like terms before isolating the variable.