Answer:
-7x(x + 4)
Step-by-step explanation:
Not sure exactly what you're doing with this, but I know you're not solving it for x because there's no " = " there so I am assuming you're simplifying it as much as possible. I'm going with that.
First thing is to distribute through the parenthesis by multiplying 4x by 3x and then 4x by -7 to get:
[tex]12x^2-28x-19x^2[/tex]
Now combine like terms to get
[tex]-7x^2-28x[/tex]
The last thing you could do now is pull out what's common between each of those terms which is -7x. When you do that, you're left with
-7x(x + 4)
