Solve the rational equation: 4/(x - 2) = 3/(x + 1).
Answer and explanation
Correct answer: B. x = -10
- Step 1: Cross-multiply: 4(x + 1) = 3(x - 2). Step 2. Expand: 4x + 4 = 3x - 6. Step 3. Subtract 3x and subtract 4: x = -10. Step 4. Check domain restrictions: x != 2 and x != -1, so x = -10 is valid. Answer: x = -10. Why not the others: Positive 5 or 8 occur when sign errors are made in cross-multiplication; -7 results from miscalculating -6 - 4.
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