Factories:

(2x + 5y)2 – 1

Given,


(2x + 5y)2 – (1)2


= (2x + 5y)2 – (1)2


By using the formula a2 – b2 = (a + b)(a – b)


We get,


(2x + 5y)2 – (1)2 = (2x + 5y)2 – (1)2


= {(2x + 5y) + 1}{(2x + 5y) – 1}


= (2x + 5y + 1)(2x + 5y – 1)


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