SOLUTION: The sum of an integer and twice its square root is 323. What is the integer?

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Question 530223: The sum of an integer and twice its square root is 323. What is the integer?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Obviously the square root is also an integer.
Let the square root be r
The number is r%5E2
r%5E2%2B2r=323
Completing the square,
r%5E2%2B2r%2B1=324
%28r%2B1%29%5E2=18%5E2
The solutions to that equation are
r%2B1=18 so that r=17 and r%5E2=289 would be the number or
r%2B1=-18 so that r=-19
but obviously that does not work, because by square root of x we usually understand the positive number that squared equals x.
So, while %28-19%29%5E2=361 complies with
361%2B2%2A%28-19%29=323, I don't think -19
would be called the square root of 361.
We would reserve that name for 19