The work of a student trying to solve the equation 3(4x − 2) = 9 + 2x + 5 is shown below:


Step 1: 3(4x − 2) = 9 + 2x + 5

Step 2: 12x − 2 = 14 + 2x

Step 3: 12x − 2x = 14 + 2

Step 4: 10x = 16

Step 5: x = 1.6


In which step did the student first make an error and what is the correct step?


A.) Step 2: 12x − 2 = 4 + 2x

B.) Step 2: 12x − 6 = 14 + 2x

C.) Step 3: 12x + 2x = 14 + 2

D.) Step 3: 12x − 2x = 14 − 2

Verified Answer :

The answer is B because you have to multiply everything in the parenthesis 3 times -2 is -6 so 12x - 6 = 14 + 2x 

The student did a mistake in step 2 they multiply incorrectly the correct step is 12x − 6 = 14 + 2x option (B) is correct.

What is a linear equation?

It is defined as the relation between two variables, if we plot the graph of the linear equation we will get a straight line.

If in the linear equation, one variable is present, then the equation is known as the linear equation in one variable.

We have an equation:

3(4x − 2) = 9 + 2x + 5

Step 1: 3(4x − 2) = 9 + 2x + 5

Step 2: 12x − 2 = 14 + 2x

Step 2 is wrong it should be:

Step 2: 12x − 6 = 14 + 2x

After solving further:

Step 3: 12x − 2x = 14 + 6

Step 4: 10x = 20

Step 5: x = 2

Thus, the student did a mistake in step 2 they multiply incorrectly the correct step is 12x − 6 = 14 + 2x option (B) is correct.

Learn more about the linear equation here:

brainly.com/question/11897796

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