Precalculus help

How do I do this?

A function f has the property that f(2+x)=f(2-x) for all x. If f has exactly four real zeros, find their sum.

f(2+x)=f(2-x) for all x simply means that the function is mirrored in x=2. So for each zero on one side of the that line, there's a zero on the other side, and they sum to 4 (eg, if f(5)=0, then f(-1)=0, and 5+-1=4). Since it is given that are two such pairs, the total sum is 8.

>>2


Thanks :)