Chen Dewei's answer to DumbFungus's Secondary 1 Maths Singapore question.

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Chen Dewei
Chen Dewei's answer
17 answers (Tutor Details)
6804 = xy^2
Prime factorise 6804 to get 2^2 x 3^5 x 7.
Largest y^2 possible is (2x3x3)^2, so y=18, x=21.