f(x) = (x^2 - 4)/(x-2) if x not equal to 2

f(x) = k if x = 2
for which value of k is f continuous at x = 2

f(x) = x +2 (obtained by factoring the numerator and canceling "x-2"
When x=2, f(x) = 4

So make k = 4 at x=2 and you have a continuous function.