The student's claim is incorrect, and his steps contain several mistakes.
Step 1 is wrong. When multiplying 2 with (4+3x), it should be 2*4 + 2*3x = 8 + 6x.
So, the correct first step is 8x - (8 + 6x).
Then, subtract the x terms and the constants separately.
8x - 6x - 8 = 2x -8.
Therefore, 8x - 2(4+3x) is actually equivalent to 2x - 8, not to 3x.
A student claims that 8x - 2(4+3x) is equivalent to 3x. The student steps are shown below.
Expression: 8x - 2(4+3x)
Step 1: 8x - 8 + 3x
Step 2: 8x + 3x - 8
Step 3:11x - 8
Step 4: 3x .
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