Answers

2014-02-06T13:45:03+01:00
2×2×a×a-4×4×a×a+5×5×a×a
=13a∧2
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2014-02-06T22:59:42+01:00
2x2xaxa = 4a square 
4x4xaxa= 16a square 
5x5xaxa= 25a square
4a*-16a*+25a*
4a*-9a* 
= -5a*
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