Write the interval (3,20] as an inequality and using set notation

The interval written could be the domain (x-values) or the range (y-values). I can't make an equation if either one of them is given. The set notation maybe expressed in symbols of (), [], or combination of both. The () is used when the domain or range is not inclusive. Otherwise, you use the [] symbols. In this case, the domain or range starts from any number greater than 3 to 20, inclusive.