What my mistake is in this problem?

ANSWERS

2015-10-30 12:32:43

You forgot to multiple the second set with the -1 If you did you would have gotten +3x and if you add +2x you would end up with +5x

2015-10-30 12:33:58

Because there is a negative between in front of the second set of parentheses, you should distribute (multiply it) it to all of the things in the second set of parenthesis. So you get +2x^2-3x+5 once you distribute, and then you can simplify. Hope that helps :)

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