SOLUTION: find two consecutive positive integers such that the sum of their squares is 61

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Question 733314: find two consecutive positive integers such that the sum of their squares is 61
Found 2 solutions by josmiceli, rothauserc:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Call the consecutive integers +n+ and +n%2B1+
given:
+n%5E2+%2B+%28+n+%2B+1+%29%5E2+=+61+
+n%5E2+%2B+n%5E2+%2B+2n+%2B+1+=+61+
+2n%5E2+%2B+2n+-+60+=+0+
+n%5E2+%2B+n+-+30+=+0+
Looking at this, I see that +5%2A6+=+30+ and the difference is +6+-+5+=++1+,
so my guess is:
+%28+n+%2B+6+%29%2A%28+n+-+5+%29+=+0+
+n+=+-6+
+n+=+5+
I need the positive solution
+n+%2B+1+=+6+
The consecutive numbers are 5 and 6
check:
+5%5E2+%2B+6%5E2+=+25+%2B+36+
+25+%2B+36+=+61+
OK

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
let i represent a positive integer and i+1 be the consecutive integer. We know that
i squared + (i+1)squared = 61
squaring both terms
i squared + i squared + 2i + 1 = 61
combining terms and subtracting 1 from both sides of equal sign we have
2 i squared + 2i = 60
divide equation by 2
i squared + i = 30
we now have the quadratic equation
i squared + i - 30 = 0
factoring the quadratic equation, we have
( i + 6 ) * (i - 5) = 0
this gives us two equations
i + 6 = 0 and i - 5 = 0
now the integers are required to be positive so the solution is
i = 5 and i+1 = 6
and we see that
5 squared + 6 squared = 61
namely,
25 + 36 = 61