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3 years ago

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The work of a student to solve the equation 2(5y – 2) = 12 + 6y is shown below: Step 1: 2(5y – 2) = 12 + 6y Step 2: 7y – 4 = 12

+ 6y Step 3: y – 4 = 10 Step 4: y = 14 Step 5: y = 7 In which step did the student first make an error and what is the correct step? (1 point) A: Step 2: 7y – 4 = 6 + 3y B: Step 2: 10y – 4 = 12 + 6y C; Step 3: 5y – 2 = 2(10 + 3y) D: Step 3: 2(5y – 2) = 10 + 3y

2 answers:

kirza4 [7]3 years ago

7 0

2(5y - 2) = 12 + 6y
7y - 4 = 12 + 6y ⇒ wrong, it has to be: 10y - 4 = 12 + 6y

so the correct answer is B

gogolik [260]3 years ago

3 0

Answer:

Option B

Step 2: $10y-4=12+6y$

Step-by-step explanation:

We are given that an equation

$2(5y-2)=12+6y$

We are given steps which are solved by student .We have to find the first error he makes in her/his steps and correct it.

Step1: $2(5y-2)=12+6y$

Step 2: $10y-4=12+6y$

But student did in step 2: $7y-4=12+6y$

So , he makes error in step 2

Step 3: $10y-6y=12+4$

Step 4: $4y=16$

Step 5: $y=\frac{16}{4}=4$

Hence, option B is true , step 2: $10y-4=12+6y$

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# # #

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