Solve 3x + 7 = 31.
Answer and explanation
Correct answer: B. x = 8
- Step 1: Subtract 7 from both sides: 3x = 24.
- Step 2: Divide by 3: x = 8.
Answer
x = 8.
Why not the others: x = 12 divides 24 by 2, x = 11 is 31 - 20 and x = 6 divides 24 by 4.
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