Factories:

16a2 – 225b2

We have,


16a2 – 225b2


= (4a)2 – (15b)2


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


We get,


16a2 – 225b2 = (4a)2 – (15b)2


= (4a + 15b)(4a – 15b)


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