9(m+n)^2-16(m-n)^2

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9(m+n)^2-16(m-n)^2
9(m+n)^2-16(m-n)^2

9(m+n)^2-16(m-n)^2
9(m+n)^2-16(m-n)^2
=[3(m+n)+4(m-n)]×[3(m+n)-4(m-n)]
=(3m+3n+4m-4n)×(3m+3n-4m+4n)
=(7m-n)(7n-m)

9(m+n)^2-16(m-n)^2
=[3(m+n)+4(m-n)][3(m+n)-4(m-n)]
=(3m+3n+4m-4n)(3m+3n-4m+4n)
=(7m-n)(7n-m)