Find two consecutive odd numbers whom sum of square is 130.
Answers
Solution:-
Let the two Odd Consecutive Numbers be ( 2x + 1) and ( 2x +3).
A.T.Q.
=) ( 2x + 1)² + ( 2x + 3)² = 130
=) 4x² + 1 + 4x + 4x² + 9 + 12x = 130
=) 8x² + 16x + 10 - 130 = 0
=) 8 ( x² + 2x - 8) = 0
=) x² + 2x - 8 = 0
=) x² + ( 4 - 2)x - 8 = 0
=) x² + 4x - 2x - 8 = 0
=) x ( x + 4) -2 ( x + 4) = 0
=) ( x + 4) ( x - 2)
=) [ x = -4 ] and [ x = 2 ].
Hence,
The Two Consecutive Odd Numbers are;
For [ x = -4 ]
( x + 3) = ( -4 + 3 ) = -1
( x + 5) = ( -4 + 5) = 1
For [ x = 2]
( x + 3) = 5
( x + 5) = 7
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Let x be an odd number
Then the second number will be x+2
According to the question,
x² + (x+2)² = 130
x² + x² + 4x + 4 = 130
2x² + 4x + 4= 130
2x²+4x + 4 - 130 = 0
2x² + 4x - 126 = 0
Dividing the equation by 2
x² + 2x - 63 = 0
x² + 9x - 7x - 63 = 0
x(x+9) -7(x+9) = 0
(x+9)(x-7) = 0
This implies
x = -9
x = 7
Since, x is a positive integer, x = -9 has to be ignored,
Hence, x = 7
x + 2 = 9
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