Pythagoras was born about 582 bc. isaac newton was born in 1643 ad. how many years apart were they born.?

2,225 years apart.
You have to add the two numbers because BC or BCE is 582 years before the common era. 1643 is 1643 AD.
If you were to draw a number line, it would be like so...
|582|1643|
^BC or BCE^ ^AD^
The space between them add up to 2,225 years apart.
Sorry if I wasn't clear. Hope it was helpful though.