Teachers are usually like that because they're required to teach you that specific way of doing a problem. If they don't, then they technically didn't do their job. Kinda dumb but it's the way they're supposed to do it
Nah however you can solve a problem should be fine
While I had a few teachers like this way back in highschool, most of them encouraged making things easier for yourself by using shortcuts
I don't know how, but you used the wrong formula and got the correct answer
@TheStarHawk, "You get an F"
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