If x - 2 = 3, then what is the value of x?

Appeared in: RML MAINS 2025

Explanation

The fundamental principle for solving this equation is to isolate the variable 'x'.
To isolate 'x' from 'x - 2', the inverse operation must be performed, which is adding 2.
To keep the equation balanced, this operation must be done on both sides of the equal sign.
Adding 2 to both sides of 'x - 2 = 3' results in 'x - 2 + 2 = 3 + 2'.
Simplifying the expression gives the final answer, x = 5.

Option A: Substituting x = 1 into the equation gives 1 - 2 = -1, which does not equal 3.
Option B: Substituting x = 2 into the equation gives 2 - 2 = 0, which does not equal 3.
Option C: Substituting x = 3 into the equation gives 3 - 2 = 1, which does not equal 3.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Solving a simple linear equation with one variable as background academic context rather than a clinical decision trigger.
Basic algebra is a foundational numeracy skill essential for nurses to perform accurate medication dosage calculations, set IV drip rates, and convert between different units of measurement.
For example, a nurse might use a similar algebraic principle to calculate the number of tablets to administer if a doctor orders 750 mg of a drug, and it is available in 250 mg tablets (250 * x = 750).
What if the equation was x * 2 = 6? The inverse operation would be division. Dividing both sides by 2 would yield x = 3.

How to Approach the Question

First, identify the goal of the question, which is to find the value of the unknown variable 'x'.
Analyze the given equation: x - 2 = 3. Observe the operation being performed on the variable; in this case, 2 is being subtracted from x.
To isolate 'x', apply the inverse operation to both sides of the equation. The inverse of subtraction is addition.
Add 2 to both sides: x - 2 + 2 = 3 + 2.
Simplify the equation to find the value of x: x = 5.
As a final step, verify your answer by substituting it back into the original equation (5 - 2 = 3) to ensure it holds true.

Concept Tested & Keywords

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