Question 23865
7Z-3Z^2+9Z
First put the equation in correct order;
{{{-3z^2}}}+9z+7z
Now add together the terms that are exactly alike;
9z+7z=16z
you can not add {{{-3z^2}}} to them because it is not the same:
so you end with;
{{{-3z^2}}}+16z
Hope you understand
=)