Answer
$-5b^3+15b^2+24b-16$.
Work Step by Step
The given expression is
$=(4-b)(5b^2+5b-4)$
Distribute $(5b^2+5b-4)$ to each term of $(4-b)$.
$=4(5b^2+5b-4)-b(5b^2+5b-4)$
Use distributive property.
$=4(5b^2)+4(5b)+4(-4)-b(5b^2)-b(5b)-b(-4)$
Multiply.
$=20b^2+20b-16-5b^3-5b^2+4b$
Combine like terms.
$=15b^2+24b-16-5b^3$
Standard form.
$=-5b^3+15b^2+24b-16$
Hence, the product is $-5b^3+15b^2+24b-16$.
