Algebraic equations and their corresponding solutions.

Let’s go through each equation one by one and solve for x. We’ll do this step by step, just like you would on paper.

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1. 2x + 3 = 21

Subtract 3 from both sides:
→ 2x = 18
Divide by 2:
→ x = 9 ✔

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2. 3 + 2x = 21

Same as above — order doesn’t matter in addition.
Subtract 3:
→ 2x = 18
Divide by 2:
→ x = 9 ✔

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3. 2x - 3 = 21

Add 3 to both sides:
→ 2x = 24
Divide by 2:
→ x = 12 ✔

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4. 3 - 2x = 21

Subtract 3 from both sides:
→ -2x = 18
Divide by -2:
→ x = -9 ✔

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5. 2x + 4 = 21

Subtract 4:
→ 2x = 17
Divide by 2:
→ x = 8.5 ✔

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6. 2x + 23 = 21

Subtract 23:
→ 2x = -2
Divide by 2:
→ x = -1 ✔

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7. (x/2) + 3 = 21

Subtract 3:
→ x/2 = 18
Multiply by 2:
→ x = 36 ✔

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8. 3x + 3 = 21

Subtract 3:
→ 3x = 18
Divide by 3:
→ x = 6 ✔

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9. 6x + 3 = 21

Subtract 3:
→ 6x = 18
Divide by 6:
→ x = 3 ✔

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10. (x/4) + 3 = 21

Subtract 3:
→ x/4 = 18
Multiply by 4:
→ x = 72 ✔

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All the given answers are correct! Each one was solved properly using basic algebra steps: isolate the term with x, then divide or multiply to get x alone.

Final Answer: All provided solutions are correct.