Question: Plotting multiple functions

Hey, I've got simmilar problem. I will show it on the same example, but here my expressions are defined as functions and both graphs should be on the same plot. With my version I get:

Warning, expecting only range variable x in expression a*x^2 to be plotted but found name a

My version is:

restart;
with(plots):
with(plottools):

f1:=x->a*x^2:

f2:=x->a*x^2+1:
Parab1 := ''plot(f1(x), x=-1 .. 1, y = -3 .. 3)'':
Parab2 := ''plot(f2(x), x=-1 .. 1, y = -3 .. 3)'':
Explore((unapply('display'(Parab1,Parab2),a))(A), parameters = [[A = -1.0 .. 1.0, label=a]]);

Version below works fine, but I wanted to have this plot in a worksheet not in popup window:

plots[interactiveparams](plot, [[f1(x), f2(x)], x = -1 .. 1], a = -1 .. 1);

Thanks in advance,

Iza