I really doesn't matter, but if you're writing an essay or something, keep all words that can have hyphens, either wil hyphens or without them. My point is that you want to be consistent.
Hyphens not needed
There are no hyphens in the word ago.
You use hyphens to make compound words that are not recognizable in common usage.
It changes the hyphens into end dashes.
If you're using the phrase as an adjective (example "This easy-to-use remote is great!") then it will definitely need the hyphens. Otherwise, the hyphens are incorrect.
It changes the hyphens into end dashes.
no hyphens - 57 years old is what you are.
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hyphen
no
no