What is the minimum value of a+b+c+d if a^2-b^2+cd^2=2022?

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anemone
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Here is this week's POTW:

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If ##a,\,b,\,c## and ##d## are non-negative integers and ##a^2-b^2+cd^2=2022##, find the minimum value of ##a+b+c+d##.

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Thanks for the interesting problem. I guess
[tex]a=1,b=2,c=1,d=45;\ a+b+c+d=49[/tex]
I would like to know the right answer.
 
anuttarasammyak said:
Thanks for the interesting problem. I guess
[tex]a=1,b=2,c=1,d=45;\ a+b+c+d=49[/tex]
I would like to know the right answer.
I am sorry. Your guess is incorrect.

I will wait a bit longer before posting the answer to this POTW, just in case there are others who would like to try it out.
 
The best I can do for now is:$$a = 17, b = 1, c = 6, d = 17; \ a + b + c + d = 41$$
 
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Well, I feel a bit guilty answering as it’s been an (extremely) long time since I was at school! However:
##a=0, b=1, c=7, d=17##
##a+b+c+d = 25##
 
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Opps! I didn't see @Steve4Physics 's answer above soon enough. Why can't I delete my wrong answer (27)?
 
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