Question 61962
Factor the polynomial
This is a little tricky, notice that the first three terms are a perfect square trinomial {{{u^2+2uv+v^2=(u+v)^2}}} 
{{{4a^2+4ab+b^2-9}}}
{{{(2a)^2+2(2a)(b)+(b)^2-9}}}  See what I mean, u=2a, v=b.
{{{(2a+b)^2-9}}}  Now you have the difference of squares: {{{u^2-v^2=(u+v)(u-v)}}}
{{{(2a+b)^2-(3)^2}}} u=2a+b, v=3
{{{((2a+b)+3)((2a+b)-3)}}}
{{{highlight((2a+b+3)(2a+b-3))}}}
Happy Calculating!!!