please simplify -11x^2+16x

Ok, what you have to do is to factorise the common terms, putting them outside brackets, and the rest of terms into brackets. I'll give you an example;

2x^2 - 4 = 2(x^2 - 2)

Do you see? 2x^2 could be divided by 2, but so did 4. So, 2 was a factor of both 2x^2 and 4, and I put it outside brackets.

-3x^2-5x = -x(3x+5)

As you can see here, there is -x common, so, I put it outside brackets.

Can you now try your question and post the answer back? :)