metrics question

[thraxrules]

Can anyone prove this theorem please?
let (X,d) be a metric space, let x \in X , and let 0<\delta<\epsilon . Then cl(B(x,delta)) \subset B(x,epsilon)

[talolard]

Assume otherwise that is chose some y that is in the closure of B(x, eps) but is not in B(x, delt). Now use the triangle inequality that is required of the metric.