1. Consider the Letter Frequency
* a: 2 times
* d: 1 time
* e: 1 time
* g: 2 times
* r: 1 time
2. Start with the Smallest Words
* 1-letter words: a, d, e, g, r (5 words)
* 2-letter words: ag, ar, da, de, ga, ge, ra, re (8 words)
* 3-letter words: age, rag, dag, ear, red, (5 words)
3. Longer Words
* 4-letter words: grade, (1 word)
* 5-letter words: dagger, (1 word)
4. Don't Forget Proper Nouns
It's possible there are proper nouns (names) that can be formed, but without a dictionary, those are harder to find.
5. Total Count
Adding up the words we've found: 5 + 8 + 5 + 1 + 1 = 20 words
Important Note: This is not an exhaustive list. There might be more obscure words or proper nouns that could be formed. Dictionaries and word lists can be helpful for a complete answer.