Question

What is the product of the polynomials below?

(7x2 + 9x + 8)(9x3 + 7x)







A.

63x6 + 81x4 + 121x3 + 63x2 + 56x








B.

63x5 + 153x4 + 112x3 + 56x








C.

63x5 + 81x4 - 121x3 + 63x1 + 56x








D.

63x5 + 81x4 + 121x3 + 63x2 + 56x

Answer 1

\(\Large \color{MidnightBlue}{\Rightarrow (7x^2 + 9x + 8)(9x^3 + 7x)
}\)
\(\Large \color{MidnightBlue}{\Rightarrow 9x^3(7x^2 + 9x + 8) + 7x(7x^2 + 9x + 8) }\)

Answer 2

would that be c

Answer 3

hello I need HELP

Answer 4

No, it isn't C. Did you multiply it out and collect the terms?

Answer 5

YEAA I DID

Answer 6

So how could you have gotten negative terms as shown in C when all your original multipliers are positive?

Answer 7

WELL ION KNOW HOW TO DO IT ' MUST BE DID SUMN WRONG

Answer 8

ok, let's start with what @ParthKohli showed up above. The expression can be written as\[{ 9x^3(7x^2 + 9x + 8) + 7x(7x^2 + 9x + 8) }\]Let's just multiply out everything. what is \[9x^3 \times 7x^2\]?

Answer 9

hint \[x^a \times x^b=x^{a+b}\]