Question 1117533
{{{(y+3)^2-4y^2=y^2+6y+9-4y^2}}}
{{{(y+3)^2-4y^2=-3y^2+6y+9}}}
{{{(y+3)^2-4y^2=-3(y^2-2y-3)}}}
{{{(y+3)^2-4y^2=-3(y+1)(y-3)}}}