the sum of the squares of two consecutive odd NUMBERS is 394.find the numbers
Answers
Answered by
104
Let the two consecutive odd numbers be x and x+2
X² + (X+2)² = 394
X² + X² + 4X + 22 = 394
2X² + 4X + 4 = 394
X² +2X =(394 - 4)/2
X² + 2X = 195
X²+2X - 195 = 0
X² + 15X - 13X -195 = 0 .
X( X + 15 ) - 13( X + 15 ) = 0
( X + 15 ) ( X - 13 )
===================================================
x+15=0
x=-15
---------------------------------------------------
x-13=0
x=+13
---------------------------------------------------
We are taking the value of x to be 13 as it is a positive number.
And (x+2)=13+2 =15
Hence, the two consecutive numbers are 13,15.
X² + (X+2)² = 394
X² + X² + 4X + 22 = 394
2X² + 4X + 4 = 394
X² +2X =(394 - 4)/2
X² + 2X = 195
X²+2X - 195 = 0
X² + 15X - 13X -195 = 0 .
X( X + 15 ) - 13( X + 15 ) = 0
( X + 15 ) ( X - 13 )
===================================================
x+15=0
x=-15
---------------------------------------------------
x-13=0
x=+13
---------------------------------------------------
We are taking the value of x to be 13 as it is a positive number.
And (x+2)=13+2 =15
Hence, the two consecutive numbers are 13,15.
Answered by
108
Hi friend!!
Let the two consecutive odd numbers be x and x+2
As per question,
x²+(x+2)² = 394
x²+x²+4x+4 = 394
2x²+4x = 394-4
2x²+4x = 390
2(x²+2x) = 390
x²+2x = 390/2
x²+2x-195 =0
x²+15x-13x-195 = 0
x(x+15)-13(x+15) = 0
(x+15)(x-13) = 0
x+15 = 0 ; x = -15
x-13 = 0 ; x = 13
If x = -15,then the other number is
x+2 = -15+2 = -13
If x = 13 then the other number is
x+2 = 13+2 = 15
Therefore, the numbers are
» -15 and -13
» 13 and 15
We can take even negative numbers because square of a negative number is positive.
Hope it helps,,...
Let the two consecutive odd numbers be x and x+2
As per question,
x²+(x+2)² = 394
x²+x²+4x+4 = 394
2x²+4x = 394-4
2x²+4x = 390
2(x²+2x) = 390
x²+2x = 390/2
x²+2x-195 =0
x²+15x-13x-195 = 0
x(x+15)-13(x+15) = 0
(x+15)(x-13) = 0
x+15 = 0 ; x = -15
x-13 = 0 ; x = 13
If x = -15,then the other number is
x+2 = -15+2 = -13
If x = 13 then the other number is
x+2 = 13+2 = 15
Therefore, the numbers are
» -15 and -13
» 13 and 15
We can take even negative numbers because square of a negative number is positive.
Hope it helps,,...
Similar questions