Answers

2016-06-25T15:27:59+08:00
I think you need to use the FOIL method.
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2016-06-25T15:59:00+08:00
1.3x²+21
2.2s²-8
3.w²+10w+21
4.x²+7x-18
5.2t²+9t-5
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