Add: (3x2 - 5x + 6) + (9 - 8x - 4x2)

A)
12x2 - 13x + 2


B)
7x2 + 3x - 3


C)
7x2 - 13x + 15


D)
-x2 - 3x + 15


E)
-x2 - 13x + 15

Respuesta :

Add: (3x2 - 5x + 6) + (9 - 8x - 4x2)
The givens should be arranged first before we can start answering.
    3x2 - 5x + 6 plus
   -4x2 - 8x + 9
= -x2  - 13x +15
Therefore, the answer to the question is E) -x2  - 13x +15

Answer: [tex]E) -x^2-13x+15[/tex] .

Step-by-step explanation:

To add : [tex](3x^2 - 5x + 6) + (9 - 8x - 4x^2)[/tex]

[tex]=3x^2 - 5x + 6+ 9 - 8x - 4x^2[/tex]

This can be re-written as :

[tex]3x^2-4x^2-5x-8x+6+9[/tex]

Combine like terms as

[tex]=(3-4)x^2-(5+8)x+15\ \ [\because (-)(+)=(-)]\\\\=-x^2-13x+15[/tex]

Therefore, [tex](3x^2 - 5x + 6) + (9 - 8x - 4x^2)=-x^2-13x+15[/tex]

Hence, the correct option is [tex]E) -x^2-13x+15[/tex] .