## College Algebra (11th Edition)

$20-60i$
Combine using difference of squares. $(9-i^2)(2-6i)$ Use the FOIL method to multiply the binomials. $18-54i-2i^2+6i^3$ Substitute $-1$ for $i^2$. $18-54i-2(-1)+6i(-1)$ Add/subtract like terms. $20-60i$