Question 1185609
25(a-2b)^2 - 4(a+b)^2
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It's a difference of 2 squares.
= {{{(5(a-2b) + 2(a+b))*(5(a-2b) - 2(a+b))}}}
= {{{(5a-10b + 2a+2b)*(5a-10b -2a-2b)}}}
= {{{(7a - 8b)*(3a - 12b)}}}
= {{{3(7a - 8b)*(a - 4b)}}}