A student attempted to generate an equivalent expression using the distributive property, as shown below:6(m + 3) = 6m + 3What was the mistake made?A. 6 was not multiplied by mB. Incorrect sign was used for the first termC. Incorrect sign was used for the second termD. 6 was not multiplied by 3

Short Answer: D
Look at them one at a time

Choice A
The result of multiplying 6 and m together (which is what you are supposed to do is 6m). This step is correct.

Choice B
There are no minus signs anywhere, either outside or inside the brackets, B is incorrect. Minus signs cannot be manufactured out of thin air. You need a reason.

Choice C
Same as B.

D is the correct answer. Both sides of a plus or minus sign have to be multiplied by what is outside the brackets. The plus sign cannot be destroyed unless you started out with something like

6 ( 4m + 3m) which = 24m + 18m = 42m But you could have combined like terms in the beginning.
6 * 7m = 42m 

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