AlgebraEasy–MediumSolving a sum-and-difference system
Algebra practice question
Two numbers have a sum of 13 and a difference of 3. What is the larger number?
- A. 8Correct
- B. 5
- C. 10
- D. 16
Answer: A. 8
Adding x + y = 13 and x − y = 3 gives 2x = 16, x = 8.
Why the other answers are wrong
- B. 5
- 5 is the smaller number.
- C. 10
- 10 is 13 − 3, forgetting to halve.
- D. 16
- 16 is 2x, not x.
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