Here

b = \(\sqrt{a}\)

or we can write as \(b^2 = a\)

Now c = a + b

or c = \(b^2\) + b

or c= b(b+1) ; now looking at the equation we need the value b as two consecutive integer then only the equation will satisfy.

Now looking at the option we find two options :-

30 as one possible option because 5 * 6 = 30 ; 5 and 6 are two consecutive integer

72 is another possible option because 8 * 9 = 72 ; 8 and 9 are two consecutive integer
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