Respuesta :

Answer:

b = -34

Step-by-step explanation:

Use " ^ " to indicate exponentiation:  

( 4x - 2 ) ( x + 9 ) - 3x = ax^2 + bx + c

Perform the indicated multiplication:

4x^2 + 36x - 2x - 18 - 3x becomes

4x^2 - 34x - 18                so b = -34

Answer:

b=31 in [tex]ax^2+bx+c[/tex]

Step-by-step explanation:

Hi there!

[tex]( 4x - 2 ) ( x + 9 ) - 3x[/tex]

Our goal is to expand this equation and put it in the form [tex]ax^2+bx+c[/tex]. Firstly, multiply the first two binomials (in the parentheses):

[tex]= 4x(x+9)-2(x+9)-3x\\= 4x^2+36x-2(x+9)-3x\\= 4x^2+36x-2x-18-3x[/tex]

Now, we can combine like terms (terms with like variables):

[tex]= 4x^2+36x-2x-3x-18\\= 4x^2+31x-18[/tex]

Now, in this equation, we can easily identify that 31 is the value of b in [tex]ax^2+bx+c[/tex].

I hope this helps!