Question 151775: It is an odd two-digit number,the sum of its digits is 8,the sum of the squares of its digits is 50. What is it?
Found 2 solutions by prasd7982, jojo14344:
Answer by prasd7982(1)   (Show Source):
You can put this solution on YOUR website! It is an odd two-digit number,the sum of its digits is 8,the sum of the squares of its digits is 50. What is it?
ANS :my ans is either 71 or 17
Answer by jojo14344(1513) (Show Source):
You can put this solution on YOUR website! The answer is right,  or  (shown in Answer#111569)
But we'll try to show the person who addressed the question how we arrived to that answer if you don't mind.
Let,  ----------> 1st digit
 ------------> 2nd digit
1st condition: the sum of its digit is 8,
 -----------> eqn 1
2nd condition: the squares of its digits is 50,
 -------> eqn 2
IN EQN 1 WE GET,  and substitute in eqn 2:
 ------------> working eqn
 --> divide the whole eqn by 2,
 -------> it's perfect square that equals to:
 , got 2 values:
 , 
Go back eqn 1,
 ------->  ---> 
AND,
 ------->  ----> 
SO THERE YOU GO, THE ANSWERS EITHER  OR 
To check, this time try eqn 2: use values of  or 
 ------------> 
Thank you,
Jojo
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