Question 547730
This is just taking the base function (x^2) and moving it up four units (due to the +4).   

So {{{y=x^2}}} looks like this 
{{{graph(500,500,-10,10,-10,10,x^2)}}}

and moving it up four units we get 
{{{graph(500,500,-10,10,-10,10,x^2+4)}}}