Hey can you state what's wrong in the given solution. =》

we know, zero is always equal to zero

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because, 16 - 16 = 0
and 20 - 20 = 0

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taking 4 as common from 16 - 16 and 5 as common from 20 - 20
now dividing both sides by
(4 - 4)

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=》
because, (4 - 4) in denominators of both sides cancels out (4 - 4) in numerator of both sides.

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we know, 4 = 2 + 2 , so plugging (2 + 2) in place of 4

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