Substituting back is one of the easiest and best ways to check your answers in linear equations. Here’s how it works:

1. Solve the Equation: First, you find a value for your variable. Let’s say you found $x = 3$. Great job! You’ve done the hard part!

2. Substitute Back: Now, take that value and put it back into the original equation. For example, if your original equation was $2x + 4 = 10$, you would replace $x$ with $3$ to see if both sides of the equation match.

3. Check for Balance: Now, do the math:

   • $2(3) + 4 = 6 + 4 = 10$.

   Since both sides equal $10$, your answer is correct!

This not only helps you know that your answer is right, but it also strengthens your understanding of the equation.

Getting into the habit of checking your work this way can help you avoid easy mistakes!