can yall help me with this problem

[Mamluke13]

2x + 3)(x2− x − 5)

= (2x)(x2 − x − 5) + (3)(x2 − x − 5)

= (2x3 − 2x2 − 10x) + (3x2 − 3x − 15)

= 2x3 + x2 − 13x − 15

This time we could collect together some like terms. There was:

−2x2 + 3x2 = x2

and

−10x − 3x = −13x

this is where i get mixed how does it end up being addition
(2x + 3)(x2− x − 5)
2x(x2− x − 5) + 3)(x2− x − 5)
(2x3 - 2x2 -10x) + (3x2 - 3x -15)

 

[Steven G]

It ends up being addition because you have + 3(x^2− x − 5) = +(3x^2 -3x -5). Is that what you are asking?

Please use ^for powers. 3x2 = 6x, not 3x^2

 

[lookagain]

this is where i get mixed how does it end up being addition
(2x + 3)(x2− x − 5)
2x(x2− x − 5) + 3)(x2− x − 5) <---------- You have mismatched parentheses.
(2x3 - 2x2 -10x) + (3x2 - 3x -15)

Maybe you got mixed up because of the incorrect close parenthesis that you typed immediately
after the "3." At the time that multiply through by the 2x and the 3, respectively, then drop the
parentheses. I recommend you write like terms near each other before combining them.
Again, use the "^" for exponentiation :

(2x + 3)(x^2 - x - 5) =
2x(x^2 - x - 5) + 3(x^2 - x - 5) =
2x^3 - 2x^2 - 10x + 3x^2 - 3x - 15 =
2x^3 - 2x^2 + 3x^2 - 10x - 3x - 15 =
2x^3 + x^2 - 13x - 15