Answer: [tex]36z^2+12z-21[/tex]
Step-by-step explanation:
You need to remember the multiplication of signs:
[tex](+)(+)=+\\(+)(-)=-\\(-)(-)=+[/tex]
In order to simplify the given the expression:
[tex](11z^2+4z-6)+(4z-7+12z^2)+(-8+13z^2+4z)[/tex]
You must distribute signs:
[tex]=11z^2+4z-6+4z-7+12z^2-8+13z^2+4z[/tex]
And finally, you must add the like terms:
[tex]=36z^2+12z-21[/tex]
