AlgebraEasy–MediumVariable on both sides with a subtraction
Algebra practice question
If 5 − x = 2x − 4, what is the value of x?
Answer: 3
Add x to both sides: 5 = 3x − 4. Add 4: 9 = 3x, so x = 3. Check: 5 − 3 = 2 and 6 − 4 = 2.
Common wrong answers
- If you answered 1
- 1 comes from 5 − x = 2x − 4 → 1 = x with the constants mishandled; collect x terms: 3x = 9.
- If you answered 9
- 9 is 3x, one step short.
- If you answered -1
- −1 comes from a sign slip in moving −x across; 5 + 4 = 3x.
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