Question 877615
Two points do not define a parabola.  Are you hoping for any parabola which will fit?  Infinite parabolas may hold any two given points.  One of your given points shows a "root", so you could begin by saying, {{{y=(x+2)(x-r)}}}.  You have one more given point which you can use by saying, {{{3=(1+2)(1-r)}}}, assuming the leading coefficient on x^2 is 1.  


Now, with the coordinate values substituted, solve for r.
{{{3(1-r)=3}}}
{{{3-3r=3}}}
{{{-3r=0}}}
{{{r=0}}}.


Your possible parabola as an equation can be {{{highlight(y=(x+2)x)}}}.
You can have any nonzero value for a for the parabola {{{y=ax(x+2)}}} and this will also work with the two given points.