Difficulty: Medium
Correct Answer: -3
Explanation:
Introduction / Context:
This question tests fraction-handling in linear equations. The core skill is to simplify bracketed fractional expressions and then eliminate denominators (by multiplying by a common multiple) to avoid arithmetic errors. Once simplified, it becomes a straightforward one-variable equation.
Given Data / Assumptions:
Concept / Approach:
Distribute (1/2) across the bracket, convert all terms to a common denominator, and then multiply both sides by the LCM of denominators (here 6) to convert to integers. This prevents mistakes from repeated fraction operations.
Step-by-Step Solution:
Start: 14/3 + (1/2)(x - 7/3) = -2x/3
Distribute 1/2: (1/2)(x - 7/3) = x/2 - 7/6
Rewrite 14/3 as /6: 14/3 = 28/6
Left side becomes: 28/6 + x/2 - 7/6 = (21/6) + x/2
So: 7/2 + x/2 = -2x/3
Multiply both sides by 6: 6*(7/2 + x/2) = 6*(-2x/3)
Left: 6*(7/2) = 21 and 6*(x/2) = 3x, so 21 + 3x
Right: 6*(-2x/3) = -4x
Equation: 21 + 3x = -4x
Add 4x: 21 + 7x = 0
So 7x = -21 => x = -3
Verification / Alternative check:
Substitute x = -3 into the original: (1/2)(-3 - 7/3) = (1/2)(-16/3) = -8/3. Then 14/3 - 8/3 = 6/3 = 2, and RHS is -2*(-3)/3 = 2. Both sides match.
Why Other Options Are Wrong:
-6 and 6 come from sign or distribution errors.
0 and 3 typically result from incorrect handling of the negative RHS or combining fractions incorrectly.
Common Pitfalls:
Forgetting to distribute 1/2 to both terms, or using an incorrect LCM when clearing denominators. Another frequent mistake is dropping the negative sign in -2x/3.
Final Answer:
x = -3
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