Find all values of $b$ for which the equations $1988x^2 + bx + 8891 = 0$ and $8891x^2 + bx + 1988 = 0$ have a common root.

Enter all the possible values of $b,$ separated by commas.
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<|im_start|>user
Find all values of $b$ for which the equations $1988x^2 + bx + 8891 = 0$ and $8891x^2 + bx + 1988 = 0$ have a common root.

Enter all the possible values of $b,$ separated by commas.
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
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user
10879
Find all values of $b$ for which the equations $1988x^2 + bx + 8891 = 0$ and $8891x^2 + bx + 1988 = 0$ have a common root.

Enter all the possible values of $b,$ separated by commas.
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