Which expression is equal to 3(x + 4) - 2(x - 5)?
Answer and explanation
Correct answer: A. x + 22
- Step 1: Expand: 3x + 12 and -2x + 10. Step 2. Collect terms: 3x - 2x = x and 12 + 10 = 22. Step 3. The expression is x + 22. Answer: x + 22. Why not the others: x + 2: This multiplies -2 by -5 as -10 instead of +10. x + 7: This multiplies -2 by -5 as +5, forgetting to multiply by 2. 5x + 2: This adds the second bracket instead of subtracting it.
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