To solve the equation $X + 3 = 7$:

1. Subtract 3 from both sides to isolate $X$: $X + 3 - 3 = 7 - 3$

2. Simplify: $X = 4$

Solution:

$X = 4$

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Would you like further clarification or details? Here are five related questions you might explore:

1. How would the solution change if the equation was $X - 3 = 7$?
2. What happens when $X + 3 = -7$?
3. Can you explain solving equations with variables on both sides, such as $X + 3 = 2X - 7$?
4. How does this apply to inequalities like $X + 3 \leq 7$?
5. How can you verify the solution of an equation?

Tip: Always check your solution by substituting it back into the original equation to confirm it satisfies the equality!