Question:
If 5x = 25, what is x?
If 5x = 25, what is x?
Show Hint
For simple equations, divide to isolate the variable and verify.
Updated On: Mar 23, 2026
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Verified By Collegedunia
The Correct Option is C
Solution and Explanation
Step-by-step Solution
-
Identify the structure of the equation.
The equation is linear and has the form a × x = b with a = 5 and b = 25. -
Choose the inverse operation to isolate x.
x is being multiplied by 5, so use the inverse operation: divide by 5. (This is valid because 5 ≠ 0.) -
Apply the Division Property of Equality to both sides.
(5x) ÷ 5 = 25 ÷ 5 -
Simplify the left side.
(5x) ÷ 5 = (5 ÷ 5) · x = 1 · x = x -
Simplify the right side.
25 ÷ 5 = 5 -
Conclude the value of x.
Therefore, x = 5. -
Verification (substitution check).
Substitute x = 5 back into the original equation:
5 × 5 = 25 ✓ (true). Hence, the solution is correct.
Alternate quick method
- Think: “What number times 5 equals 25?”
- Since 25 ÷ 5 = 5, immediately x = 5.
- This matches the algebraic result.
Common mistakes to avoid
- Dividing only one side by 5 (must divide both sides to keep equality balanced).
- Using subtraction instead of division (the inverse of multiplication is division).
Final Answer
x = 5 — this is the correct option.
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