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he work of a student to solve the equation 4(2x − 4) = 8 + 2x + 8 is shown below: Step 1: 4(2x − 4) = 8 + 2x + 8 Step 2: 6x − 8 = 16 + 2x Step 3: 6x − 2x = 16 + 8 Step 4: 4x = 24 Step 5: x = 6 In which step did the student first make an error and what is the correct step? Step 2; 8x − 4 = 2(6 + x + 6) Step 2; 8x − 16 = 16 + 2x Step 3; 6x − 2x = 16 − 8 Step 3; 6x + 2x = 16 + 8

User Jason Antman
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2 Answers

19 votes
19 votes

Answer:

4(2x-4)=8+2x+8

8x-16=16+2x

8x-2x=16+16

6xboth sides over 6

x=5.3repiting

User Chintan
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3.1k points
12 votes
12 votes

Answer:

step 2: 8x-4=2(6+x+6)

Explanation:


4(2x - 4) = 8 + 2x + 8 \\ 8x - 16 = 16 + 2x here \\ 8x - 2x = 16 + 16 \\ 6x = 32 \\ (6x)/(6) = (32)/(6) \\ x = 5

User Mahesh KP
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2.5k points