Solve 4(2x - 3) = 3x + 13.
Answer and explanation
Correct answer: D. x = 5
- Step 1: Expand the bracket: 8x - 12 = 3x + 13. Step 2. Subtract 3x and add 12 on both sides: 5x = 25. Step 3. Divide by 5: x = 5. Answer: x = 5. Why not the others: x = 3.2: This multiplies out the bracket as 8x - 3, forgetting to multiply the 3 by 4, which gives 5x = 16. x = 0.2: This subtracts 13 from both sides instead of adding it, giving 5x = 1. x = 25: This stops at 5x = 25 and never divides by 5.
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