Question

Please help!!!

Simplify.

(3x^2 + 2x + 7x^3) + (10x^2 + 6x + 9)

A) 7x^3 + 13x^2 + 8x + 9

B) 7x^3 + 30x^2 + 12x + 9

C) 13x^3 + 8x + 16x^3

D) 13x^4 + 7x^3 + 8x^2 + 9

Answer 1

`\large\boxed{A.\ 7x^3+13x^2+8x+9}`

Explanation:

`(3x^2 + 2x + 7x^3) + (10x^2 + 6x + 9)\\\\=3x^2 + 2x + 7x^3 + 10x^2 + 6x + 9\qquad\text{combine like terms}\\\\=7x^3+(3x^2+10x^2)+(2x+6x)+9\\\\=7x^3+13x^2+8x+9`

Answer 2

A) 7x^3 + 13x^2 + 8x + 9

Explanation:

(3x^2 + 2x + 7x^3) + (10x^2 + 6x + 9)

I like to line them up vertically

7x^3 +3x^2 + 2x

+ (10x^2 + 6x + 9)

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7x^3 +13x^2 +8x +9