y=3x+5 is the answer.
Since it is Parnell the leading coefficient wont change. so all you have to do is get it to match the point.
the way you will do this is by replacing x with the graph x and y with graph y and solving
11=3(2)+a
11=6+a
11-6=a
5=a
that would make the answer be y=3x+5