Question 1206053
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I hope you mean the answer in the book is {{{-(3+a)/(a+2)}}} and not {{{(-3+a)/(a+2)}}}....<br>
In the work you show, you have....<br>
{{{((2-a)(3+a))/((a+2)(a-2))}}}<br>
and then<br>
{{{(3+a)/(a+2)}}}<br>
That means you canceled the factors {{{(2-a)}}} and {{{(a-2)}}}.<br>
But those factor are not the same; they are opposites: {{{(2-a)=-1(a-2)}}}<br>
So {{{((2-a)(3+a))/((a+2)(a-2))=((-1)(a-2)(3+a))/((a+2)(a-2))=-(3+a)/(a+2)}}}<br>