easy equation curve near points



for example, I have these points:
p:[[0.7, 0.5],[1.21, 1.33], [-0.42,0.17],[-0.93,0.87], [-0.79, 0.5], [-0.55, 0.36], [-0.27, 0.05], [0.27, 0.11], [0.5, 0.25]];

I don't want to get a complex equation like lagrange(p)..

the question is: is possibile to give a command and get an equation like y=x^2 ?