Question

simplify (10x^2-8x-1) (4x^2-8x-5)

Answer 1

Hint:

(10x^2-8x-1) (4x^2-8x-5)

expands out to

10x^2(4x^2-8x-5) - 8x(4x^2-8x-5) - 1(4x^2-8x-5)

Answer 2

Distribute that and combine like terms

Answer 3

You're going to take each term in one polynomial and multiply it by all the other terms in the other polynomial, and then add everything together:
\((10x^2-8x-1)(4x^2-8x-5)=\\40x^4-80x^3-50x^2-32x^3+64x^2+40x-4x^2+8x+5=\\
40x^4-112x^3+10x^2+48x+5 \)