What must be added each of the following expression to make it a whole square?
(i) 
(ii) 
(i) 
(2x)2 – 2 (2x) (3) + 32 – 32 + 7
= (2x – 3)2 – 9 + 7
= (2x – 3)2 – 2
Hence, 2 must be added to the expression in order to make a whole square
(ii) 
(2x)2 – 2 (2x) (5) + 52 – 52 + 20
= (2x – 5)2 – 25 + 20
= (2x – 5)2 – 5
Hence, 5 must be added to the expression in order to make it a whole square
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