SOLUTION: find two onsecutive positive even numbers the sum of whose squares is 20.

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Question 301438: find two onsecutive positive even numbers the sum of whose squares is 20.
Found 3 solutions by vleith, Alan3354, checkley77:
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
You can do a bunch of algebra to solve
n%5E2+%2B+%28n%2B2%29%5E2+=+20
Or you can use a little 'common sense' and realize
- number squared are always positive
- 20 is a small number (between 4^2 and 5^2
- so use trial and error with even numbers
Try 2 and 4
2^2 = 4
4^2 = 16
4+16= 20
done

Answer by Alan3354(69443) About Me  (Show Source):
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
x^2+(x+2)^2=20
x^2+x^2+4x+4=20
2x^2+4x+4-20=0
2(x^2+2x-16)=0
2(x^2+2x-8)=0
2(x+4)(x-2)=0
x-2=0
x=2 ans.
2+2=4 ans.
Proof:
2^2+4^2=20
4+16=20
20=20