Question

What is the product of the polynomials shown below?

Answer 1

Answer:

B. 14x^3+39x^2+18x+20

Step-by-step explanation:

Given polynomials are:

$(7x^2+2x+4)(2x+5)\\For\ product\\(2x+5)(7x^2+2x+4)\\= 2x(7x^2+2x+4)+5(7x^2+2x+4)\\= 14x^3+4x^2+8x+35x^2+10x+20\\Combining\ alike\ terms\\= 14x^3+4x^2+35x^2+8x+10x+20\\=14x^3+39x^2+18x+20$

The product of given polynomials is:

14x^3+39x^2+18x+20

Hence, Option B is correct ..

Answer 2

Answer:

B.  14x^3 + 39x^2 + 18x + 20.

Step-by-step explanation:

(7x^2 + 2x + 4)(2x + 5)

= 2x(7x^2 + 2x + 4) + 5(7x^2 + 2x + 4)

Distribute over the 2 parentheses:

= 14x^3 + 4x^2 + 8x + 35x^2 + 10x + 20

Add like terms:

= 14x^3 + 39x^2 + 18x + 20.