Solve this following

Question:

If the equation, $x^{2}+b x+45=0(b \in R)$ has conjugate complex roots and they satisfy $|z+1|=2 \sqrt{10}$, then

  1. $b^{2}-b=42$

  2. $b^{2}+b=12$

  3. $b^{2}+b=72$

  4. $b^{2}-b=30$


Correct Option: , 4

Solution:

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