Algebra — Find the Error: Linear Equations — Dynamic

Algebra — Find the Error: Linear Equations — Dynamic Practice. Practice questions to deepen understanding of identifying errors in solving linear equations. Online math practice with full solutions and step-by-step explanations.

Dynamic practice spotting common mistakes when solving linear equations — sign errors and incorrect operations across the equals sign.

35 questions

Question 1

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(10x + 4 = 54\)

One of the solution steps is wrong. Which step?

\(10x = 54\)
\(x = 54 / 10\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(10x = 54\) ❌
\(x = 54 / 10\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 2

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(8x + 4 = 68\)

One of the solution steps is wrong. Which step?

\(8x = 68\)
\(x = 68 / 8\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(8x = 68\) ❌
\(x = 68 / 8\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 3

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(6x + 6 = 12\)

One of the solution steps is wrong. Which step?

\(6x = 0\)
\(x = 0 / 6\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(6x = 0\) ❌
\(x = 0 / 6\) ✓

📌 Explanation:

In step 1, an error was made: Subtracted twice — double move

Question 4

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(2x + 1 = 21\)

One of the solution steps is wrong. Which step?

\(2x = 21\)
\(x = 21 / 2\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(2x = 21\) ❌
\(x = 21 / 2\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 5

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(4x + 2 = 30\)

One of the solution steps is wrong. Which step?

\(4x = 32\)
\(x = 32 / 4\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(4x = 32\) ❌
\(x = 32 / 4\) ✓

📌 Explanation:

In step 1, an error was made: Sign not changed when moving between sides

Question 6

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(2x + 7 = 25\)

One of the solution steps is wrong. Which step?

\(2x = 25\)
\(x = 25 / 2\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(2x = 25\) ❌
\(x = 25 / 2\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 7

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(3x + 14 = 47\)

One of the solution steps is wrong. Which step?

\(3x = 33\)
\(x = 30\)

Step 2

Step 1

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 2:

\(3x = 33\) ✓
\(x = 30\) ❌

📌 Explanation:

In step 2, an error was made: Subtracted instead of dividing

Question 8

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(6x + 5 = 59\)

One of the solution steps is wrong. Which step?

\(6x = 59\)
\(x = 59 / 6\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(6x = 59\) ❌
\(x = 59 / 6\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 9

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(6x + 4 = 28\)

One of the solution steps is wrong. Which step?

\(6x = 20\)
\(x = 20 / 6\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(6x = 20\) ❌
\(x = 20 / 6\) ✓

📌 Explanation:

In step 1, an error was made: Subtracted twice — double move

Question 10

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(8x + 1 = 33\)

One of the solution steps is wrong. Which step?

\(8x = 34\)
\(x = 34 / 8\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(8x = 34\) ❌
\(x = 34 / 8\) ✓

📌 Explanation:

In step 1, an error was made: Sign not changed when moving between sides

Question 11

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(7x + 4 = 18\)

One of the solution steps is wrong. Which step?

\(7x = 14\)
\(x = 98\)

Step 2

Step 1

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 2:

\(7x = 14\) ✓
\(x = 98\) ❌

📌 Explanation:

In step 2, an error was made: Confusion between multiplication and division with coefficient

Question 12

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(4x + 12 = 36\)

One of the solution steps is wrong. Which step?

\(4x = 48\)
\(x = 48 / 4\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(4x = 48\) ❌
\(x = 48 / 4\) ✓

📌 Explanation:

In step 1, an error was made: Sign not changed when moving between sides

Question 13

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(6x + 2 = 26\)

One of the solution steps is wrong. Which step?

\(6x = 26\)
\(x = 26 / 6\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(6x = 26\) ❌
\(x = 26 / 6\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 14

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(5x + 15 = 70\)

One of the solution steps is wrong. Which step?

\(5x = 70\)
\(x = 70 / 5\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(5x = 70\) ❌
\(x = 70 / 5\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 15

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(6x + 11 = 71\)

One of the solution steps is wrong. Which step?

\(6x = 71\)
\(x = 71 / 6\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(6x = 71\) ❌
\(x = 71 / 6\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 16

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(7x + 8 = 3x + 24\)

One of the solution steps is wrong. Which step?

\(7x = 3x + 16\)
\(7x - 3x = 16\)
\(x = 16 / 4\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(7x = 3x + 16\) ❌
\(7x - 3x = 16\) ✓
\(x = 16 / 4\) ✓

📌 Explanation:

In step 1, an error was made: Partial move — forgot a term

Question 17

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(5x + 5 = 2x + 32\)

One of the solution steps is wrong. Which step?

\(5x - 2x = 32 - 5\)
\(3x = 27\)
\(x = 81\)

Step 3

Step 1

Step 2

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 3:

\(5x - 2x = 32 - 5\) ✓
\(3x = 27\) ✓
\(x = 81\) ❌

📌 Explanation:

In step 3, an error was made: Confusion between multiplication and division with coefficient

Question 18

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(9x + 9 = 3x + 63\)

One of the solution steps is wrong. Which step?

\(9x - 3x = 63 - 9\)
\(6x = 54\)
\(x = 324\)

Step 3

Step 1

Step 2

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 3:

\(9x - 3x = 63 - 9\) ✓
\(6x = 54\) ✓
\(x = 324\) ❌

📌 Explanation:

In step 3, an error was made: Confusion between multiplication and division with coefficient

Question 19

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(3x + 15 = 1x + 25\)

One of the solution steps is wrong. Which step?

\(3x - 1x = 25 - 15\)
\(2x = 10\)
\(x = 8\)

Step 3

Step 1

Step 2

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 3:

\(3x - 1x = 25 - 15\) ✓
\(2x = 10\) ✓
\(x = 8\) ❌

📌 Explanation:

In step 3, an error was made: Subtracted instead of dividing

Question 20

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(8x + 11 = 7x + 17\)

One of the solution steps is wrong. Which step?

\(8x - 7x = 17 + 11\)
\(1x = 28\)
\(x = 28 / 1\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(8x - 7x = 17 + 11\) ❌
\(1x = 28\) ✓
\(x = 28 / 1\) ✓

📌 Explanation:

In step 1, an error was made: Sign not changed when moving between sides

Question 21

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(6x + 12 = 1x + 22\)

One of the solution steps is wrong. Which step?

\(6x - 1x = 22 - 12\)
\(7x = 10\)
\(x = 10 / 7\)

Step 2

Step 1

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 2:

\(6x - 1x = 22 - 12\) ✓
\(7x = 10\) ❌
\(x = 10 / 7\) ✓

📌 Explanation:

In step 2, an error was made: Wrong combining — added coefficients instead of subtracting

Question 22

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(7x + 12 = 5x + 16\)

One of the solution steps is wrong. Which step?

\(7x - 5x = 16 - 12\)
\(2x = 4\)
\(x = 8\)

Step 3

Step 1

Step 2

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 3:

\(7x - 5x = 16 - 12\) ✓
\(2x = 4\) ✓
\(x = 8\) ❌

📌 Explanation:

In step 3, an error was made: Confusion between multiplication and division with coefficient

Question 23

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(3x + 7 = 1x + 19\)

One of the solution steps is wrong. Which step?

\(3x - 1x = 19\)
\(2x = 19\)
\(x = 19 / 2\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(3x - 1x = 19\) ❌
\(2x = 19\) ✓
\(x = 19 / 2\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 24

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(5x + 3 = 1x + 19\)

One of the solution steps is wrong. Which step?

\(5x = 1x + 16\)
\(5x - 1x = 16\)
\(x = 16 / 4\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(5x = 1x + 16\) ❌
\(5x - 1x = 16\) ✓
\(x = 16 / 4\) ✓

📌 Explanation:

In step 1, an error was made: Partial move — forgot a term

Question 25

3.00 pts

🔍 Find the mistake:
Steps in solving the equation:
\(9x + 11 = 6x + 44\)

One of the solution steps is wrong. Which step?

\(9x - 6x = 44 - 11\)
\(3x = 33\)
\(x = 33\)

Step 3

Step 1

Step 2

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 3:

\(9x - 6x = 44 - 11\) ✓
\(3x = 33\) ✓
\(x = 33\) ❌

📌 Explanation:

In step 3, an error was made: Forgot to divide — left with ax = b

Question 26

2.50 pts

🔍 Find the mistake:
Steps in solving the equation:
\(4x + 8 = 1x + 44\)

One of the solution steps is wrong. Which step?

\(4x - 1x = 44 - 8 - 8\)
\(3x = 28\)
\(x = 28 / 3\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(4x - 1x = 44 - 8 - 8\) ❌
\(3x = 28\) ✓
\(x = 28 / 3\) ✓

📌 Explanation:

In step 1, an error was made: Subtracted twice — double move

Question 27

2.50 pts

🔍 Find the mistake:
Steps in solving the equation:
\(15x + 12 = 1x + 194\)

One of the solution steps is wrong. Which step?

\(15x - 1x = 194 - 12\)
\(14x = 182\)
\(x = 182\)

Step 3

Step 1

Step 2

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 3:

\(15x - 1x = 194 - 12\) ✓
\(14x = 182\) ✓
\(x = 182\) ❌

📌 Explanation:

In step 3, an error was made: Forgot to divide — left with ax = b

Question 28

2.50 pts

🔍 Find the mistake:
Steps in solving the equation:
\(14x + 11 = 1x + 37\)

One of the solution steps is wrong. Which step?

\(14x - 1x = 37\)
\(13x = 37\)
\(x = 37 / 13\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(14x - 1x = 37\) ❌
\(13x = 37\) ✓
\(x = 37 / 13\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 29

2.50 pts

🔍 Find the mistake:
Steps in solving the equation:
\(13x + 12 = 4x + 138\)

One of the solution steps is wrong. Which step?

\(13x - 4x = 138 - 12\)
\(9x = 126\)
\(x = 117\)

Step 3

Step 1

Step 2

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 3:

\(13x - 4x = 138 - 12\) ✓
\(9x = 126\) ✓
\(x = 117\) ❌

📌 Explanation:

In step 3, an error was made: Subtracted instead of dividing

Question 30

2.50 pts

🔍 Find the mistake:
Steps in solving the equation:
\(15x + 10 = 6x + 91\)

One of the solution steps is wrong. Which step?

\(15x = 6x + 81\)
\(15x - 6x = 81\)
\(x = 81 / 9\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(15x = 6x + 81\) ❌
\(15x - 6x = 81\) ✓
\(x = 81 / 9\) ✓

📌 Explanation:

In step 1, an error was made: Partial move — forgot a term

Question 31

2.50 pts

🔍 Find the mistake:
Steps in solving the equation:
\(7x + 5 = 4x + 29\)

One of the solution steps is wrong. Which step?

\(7x = 4x + 24\)
\(7x - 4x = 24\)
\(x = 24 / 3\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(7x = 4x + 24\) ❌
\(7x - 4x = 24\) ✓
\(x = 24 / 3\) ✓

📌 Explanation:

In step 1, an error was made: Partial move — forgot a term

Question 32

2.50 pts

🔍 Find the mistake:
Steps in solving the equation:
\(4x + 9 = 1x + 33\)

One of the solution steps is wrong. Which step?

\(4x - 1x = 33 - 9\)
\(3x = 24\)
\(x = 72\)

Step 3

Step 1

Step 2

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 3:

\(4x - 1x = 33 - 9\) ✓
\(3x = 24\) ✓
\(x = 72\) ❌

📌 Explanation:

In step 3, an error was made: Confusion between multiplication and division with coefficient

Question 33

2.50 pts

🔍 Find the mistake:
Steps in solving the equation:
\(5x + 16 = 4x + 23\)

One of the solution steps is wrong. Which step?

\(5x - 4x = 23\)
\(1x = 23\)
\(x = 23 / 1\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(5x - 4x = 23\) ❌
\(1x = 23\) ✓
\(x = 23 / 1\) ✓

📌 Explanation:

In step 1, an error was made: Did not move term to other side

Question 34

2.50 pts

🔍 Find the mistake:
Steps in solving the equation:
\(7x + 14 = 1x + 32\)

One of the solution steps is wrong. Which step?

\(7x - 1x = 32 - 14\)
\(6x = 18\)
\(x = 12\)

Step 3

Step 1

Step 2

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 3:

\(7x - 1x = 32 - 14\) ✓
\(6x = 18\) ✓
\(x = 12\) ❌

📌 Explanation:

In step 3, an error was made: Subtracted instead of dividing

Question 35

2.50 pts

🔍 Find the mistake:
Steps in solving the equation:
\(13x + 10 = 7x + 52\)

One of the solution steps is wrong. Which step?

\(13x = 7x + 42\)
\(13x - 7x = 42\)
\(x = 42 / 6\)

Step 1

Step 2

Step 3

Step 4

Explanation:

🔍 Find the mistake

📌 The wrong step is step 1:

\(13x = 7x + 42\) ❌
\(13x - 7x = 42\) ✓
\(x = 42 / 6\) ✓

📌 Explanation:

In step 1, an error was made: Partial move — forgot a term