Show that n²+2n+12 is not a multiple of 121 for any integer n.

Dear Student,
We first make the assumption that n²+2n+12 is a multiple of 121.
i.e n²+2n+12=121*k(Where k is any positive integer)
i.e n²+2n+12-121*k=0.
Formula Method for Quadratic Equationax2+bx+c=0 is x=-b±b2-4ac/2a
Now, solving for n using the Formula Method, 
n= -2±484*k-44/2

Given that n is an integer, so (484k)−44 should be an integer
But it can also be written as:-

i.e n=-2±44(11k-1)/2
But this value cannot be an integer as the vaue of 44is irrational.
Therefore our assumption that 121 is a multiple of the equation is wrong.
Hence the following statement is proved.
Regards.

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