[tex]z=2.1[/tex] falls outside the region [tex]|z|<1.96[/tex], which suggests that [tex]|z|>1.96[/tex] is the rejection region for a hypothesis at a 5% significance level. (We know this because [tex]\mathbb P(|Z|<1.96)\approx0.95[/tex].) Because [tex]z[/tex] falls in the rejection region, presumably this means you are rejecting some null hypothesis. But it's difficult to say for certain without any more information.
