Question

How do you multiply `-4b(1-9b-2b^2)`?

Answer 1

`8b^3 + 36b^2 - 4b`

Explanation:

Just Distribute `-4b` and multiply with each term.
`-4b(1-9b-2b^2) = (-4b)(1) - (-4b)(9b) - (-4b)(2b^2)`

Watch out for Sign Changes, if any.
`= -4b + 36b^2 + 8b^3`

Re-order from highest power to lowest:
`= 8b^3 + 36b^2 - 4b`