Wednesday, November 7, 2012

The sum of the squares of two consecutive numbers is 145. Find the numbers.

The sum of the squares of two consecutive numbers is
145.


Let the numbers be N and N +
1


Now we have N^2 + (N +1)^2 =
145


=> N^2 + N^2 + 2N + 1 =
145


=> 2N^2 + 2N - 144 =
0


=> N^2 + N - 72 =
0


=> N^2 + 9N - 8N - 72 =
0


=> N(N + 9) - 8(N + 9) =
0


=> (N - 8)(N + 9) =
0


N can be 8 or
-9


So the two numbers are (8 , 9) or ( -8 ,
-9)
.

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