Question 1165515
<pre>
Your error is that "a" is not 0, it's -1, because if you square the
parentheses and collect terms, you get

{{{"g(x)"=-(x+1)^2-3}}}

{{{"g(x)"=-(x+1)(x+1)-3}}}

{{{"g(x)"=-(x^2+x+x+1)-3}}}

{{{"g(x)"=-(x^2+2x+1)-3}}}

The - sign changes all the signs inside the parentheses:

{{{"g(x)"=-x^2-2x-1-3}}}

{{{"g(x)"=-x^2-2x-4}}}

{{{"g(x)"=-1x^2-2x-4}}}

So you see "a" is not 0, it's -1.

I multiplied it all out to show you that a =-1, not 0. But you 
can tell it is -1 without multiplying it out if you think about it.

Edwin</pre>