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I NEED HELP ON THESE PLSS

Question 1 
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?

Question 2
A student is trying to solve the system of two equations given below:

Equation P: y + z = 6
Equation Q: 8y + 7z = 1

Which of these is a possible step used in eliminating the y-term?

1 Answer

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Question 1


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

Distributing 2 on 5y -2, we will get


10y-4=12+6y

But student get


7y-4=12+6y

So the student make an error in step 2 .

Second question


image

To get rid of y, we have to multiply first equation by -8 and add the resultant equation with equation Q .

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