## Intermediate Algebra (6th Edition)

$b=\{ -9, 9, -3, 3 \}$
The factors of $-10$ are $\{1,-10\}, \{-1,10\}, \{2,-5\}, \{-2,5\}.$ Getting the sum of these factors, then $b=\{ -9, 9, -3, 3 \}$.